Prof. Dr. Tayebeh Ameri
Academic Research Focus
- Energy generation and energy storage
- Flexible and portable (opto)electronics
- Nanomorphology and charge transport mechanisms
- Flexible and portable (opto)electronics
- Nanomorphology and charge transport mechanisms
Fields of Application
Nanomaterials, Solar Cells / Photovoltaics
Publications
17.
R Holfeuer, C Maheu, H Illner, R Hoojier, H Balakrishnan, B März, S Lotfi, H Sezen, K Müller-Caspary, T Bein, J P Hofmann, T Ameri, A Hartschuh, A Yousefiamin
Printed CsMg–ZnO ETLs achieve over 9 % efficiency in PbS quantum dot solar cells Journal Article
In: Materials Today Energy, vol. 48, pp. 101813, 2025, ISSN: 2468-6069.
@article{nokey,
title = {Printed CsMg\textendashZnO ETLs achieve over 9 % efficiency in PbS quantum dot solar cells},
author = {R Holfeuer and C Maheu and H Illner and R Hoojier and H Balakrishnan and B M\"{a}rz and S Lotfi and H Sezen and K M\"{u}ller-Caspary and T Bein and J P Hofmann and T Ameri and A Hartschuh and A Yousefiamin},
url = {https://www.sciencedirect.com/science/article/pii/S2468606925000218},
doi = {https://doi.org/10.1016/j.mtener.2025.101813},
issn = {2468-6069},
year = {2025},
date = {2025-03-01},
journal = {Materials Today Energy},
volume = {48},
pages = {101813},
abstract = {Zinc oxide (ZnO) is a key electron transport layer (ETL) material in next-generation lead sulfide (PbS) colloidal quantum dot solar cells (CQDSCs) due to its high transparency, strong exciton binding energy, and good electron mobility. Here, we demonstrate a scalable doctor-blading printing protocol for ZnO ETLs that integrates dual defect passivation with magnesium (Mg2⁺) and caesium (Cs⁺) and employs solvent engineering to achieve uniform, defect-minimized films. Using a ternary solvent blend (methanol, chloroform, and 2-methoxyethanol) optimizes the ink's viscosity and boiling point, preventing particle migration and ensuring full substrate coverage. Our modified ZnO ink leads to improved crystallinity, smoother surfaces, and reduced trap states, boosting the fill factor (FF) and short-circuit current (Jsc). Consequently, we achieve a power conversion efficiency increase from 5.98 % to 9.53 % using a printed CsMg-ZnO film. Notably, 80 % of dual-doped devices exceeded 7.5 % efficiency, demonstrating high reproducibility and reliability. This performance enhancement underscores the effectiveness of dual metal ion treatment and solvent engineering strategies in overcoming printability challenges. Moreover, the compatibility of our approach with low-temperature processing and established coating techniques paves the way for seamless integration into large-scale manufacturing, bringing PbS CQDSCs closer to commercial viability.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Zinc oxide (ZnO) is a key electron transport layer (ETL) material in next-generation lead sulfide (PbS) colloidal quantum dot solar cells (CQDSCs) due to its high transparency, strong exciton binding energy, and good electron mobility. Here, we demonstrate a scalable doctor-blading printing protocol for ZnO ETLs that integrates dual defect passivation with magnesium (Mg2⁺) and caesium (Cs⁺) and employs solvent engineering to achieve uniform, defect-minimized films. Using a ternary solvent blend (methanol, chloroform, and 2-methoxyethanol) optimizes the ink's viscosity and boiling point, preventing particle migration and ensuring full substrate coverage. Our modified ZnO ink leads to improved crystallinity, smoother surfaces, and reduced trap states, boosting the fill factor (FF) and short-circuit current (Jsc). Consequently, we achieve a power conversion efficiency increase from 5.98 % to 9.53 % using a printed CsMg-ZnO film. Notably, 80 % of dual-doped devices exceeded 7.5 % efficiency, demonstrating high reproducibility and reliability. This performance enhancement underscores the effectiveness of dual metal ion treatment and solvent engineering strategies in overcoming printability challenges. Moreover, the compatibility of our approach with low-temperature processing and established coating techniques paves the way for seamless integration into large-scale manufacturing, bringing PbS CQDSCs closer to commercial viability.
16.
A Semerci, J Urieta-Mora, S Driessen, A Buyruk, R Hooijer, A Molina-Ontoria, B Alkan, S Akin, M Fanetti, H Balakrishnan, A Hartschuh, S Tao, N Martín, P Müller-Buschbaum, S Emin, T Ameri
The Role of Fluorine-Functionalized Organic Spacers for Defect Passivation and Low-Dimensional Phase Formation in 3D MAPI Perovskite Solar Cells Journal Article
In: Advanced Functional Materials, vol. n/a, no. n/a, pp. 2423109, 2025, ISSN: 1616-301X.
@article{nokey,
title = {The Role of Fluorine-Functionalized Organic Spacers for Defect Passivation and Low-Dimensional Phase Formation in 3D MAPI Perovskite Solar Cells},
author = {A Semerci and J Urieta-Mora and S Driessen and A Buyruk and R Hooijer and A Molina-Ontoria and B Alkan and S Akin and M Fanetti and H Balakrishnan and A Hartschuh and S Tao and N Mart\'{i}n and P M\"{u}ller-Buschbaum and S Emin and T Ameri},
url = {https://doi.org/10.1002/adfm.202423109},
doi = {https://doi.org/10.1002/adfm.202423109},
issn = {1616-301X},
year = {2025},
date = {2025-02-14},
journal = {Advanced Functional Materials},
volume = {n/a},
number = {n/a},
pages = {2423109},
abstract = {Abstract Widespread application of organic-inorganic halide perovskites (OIHP) still faces a major obstacle in mitigating moisture-induced degradation. Integrating organic spacers, as defect passivation facilitators along with low-dimensional phase (LDP) formation is an effective approach to enhance the efficiency and robustness of 3D methyl ammonium lead iodide (MAPI) in photovoltaics (PV). Here, the formamidinium cation (FA+) employing 3,5-difluorobenzene-1-carboximidamidium iodide (2F), 4-(trifluoromethyl)benzene-1-carboximidamidium iodide (3F), and 2,3,4,5,6-pentafluorobenzene-1-carboximidamidium iodide (5F) organic spacers as passivation layer in 3D/LDP OIHP solar cells is utilized. Fluorine atom position and quantity in organic spacers change the optoelectronic characteristics of the perovskites, enhancing hydrophobicity, facilitating LDP formation, and augmenting dipole moments, thereby facilitating charge separation processes. PV performance analysis reveals that 3F-treated 3D/LDP devices achieve the highest efficiency of 19.22%. Experimental results and density functional theory (DFT) studies attribute the higher performance of 3F-modified devices to effective LDP formation, enhanced passivation of defect states at perovskite surfaces and grain boundaries, the highest dipole moment and lowest band gap among the evaluated spacers. The stability tests show that, after 1000 h, 3F- and 5F-modified 3D/LDP OIHP devices retain over 85% of their initial efficiency. This research opens novel avenues for designing appropriate organic spacers to attenuate defects in 3D/LDP PV devices.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Abstract Widespread application of organic-inorganic halide perovskites (OIHP) still faces a major obstacle in mitigating moisture-induced degradation. Integrating organic spacers, as defect passivation facilitators along with low-dimensional phase (LDP) formation is an effective approach to enhance the efficiency and robustness of 3D methyl ammonium lead iodide (MAPI) in photovoltaics (PV). Here, the formamidinium cation (FA+) employing 3,5-difluorobenzene-1-carboximidamidium iodide (2F), 4-(trifluoromethyl)benzene-1-carboximidamidium iodide (3F), and 2,3,4,5,6-pentafluorobenzene-1-carboximidamidium iodide (5F) organic spacers as passivation layer in 3D/LDP OIHP solar cells is utilized. Fluorine atom position and quantity in organic spacers change the optoelectronic characteristics of the perovskites, enhancing hydrophobicity, facilitating LDP formation, and augmenting dipole moments, thereby facilitating charge separation processes. PV performance analysis reveals that 3F-treated 3D/LDP devices achieve the highest efficiency of 19.22%. Experimental results and density functional theory (DFT) studies attribute the higher performance of 3F-modified devices to effective LDP formation, enhanced passivation of defect states at perovskite surfaces and grain boundaries, the highest dipole moment and lowest band gap among the evaluated spacers. The stability tests show that, after 1000 h, 3F- and 5F-modified 3D/LDP OIHP devices retain over 85% of their initial efficiency. This research opens novel avenues for designing appropriate organic spacers to attenuate defects in 3D/LDP PV devices.
15.
M Günther, N Kazerouni, D Blätte, J D Perea, B C Thompson, T Ameri
Models and mechanisms of ternary organic solar cells Journal Article
In: Nature Reviews Materials, vol. 8, no. 7, pp. 456-471, 2023, ISSN: 2058-8437.
@article{nokey,
title = {Models and mechanisms of ternary organic solar cells},
author = {M G\"{u}nther and N Kazerouni and D Bl\"{a}tte and J D Perea and B C Thompson and T Ameri},
url = {https://doi.org/10.1038/s41578-023-00545-1},
doi = {10.1038/s41578-023-00545-1},
issn = {2058-8437},
year = {2023},
date = {2023-07-01},
journal = {Nature Reviews Materials},
volume = {8},
number = {7},
pages = {456-471},
abstract = {In ternary organic solar cells (TOSCs), three different components are mixed to form the photoactive layer, opening up opportunities to boost the power conversion efficiency \textemdash for example, by broadening the absorption range, improving the blend morphology or tuning the exciton splitting and charge extraction. Because of these possibilities, ternary systems are among the best performing OSCs and will have a crucial role in the future of organic photovoltaics. Owing to the interplay of three different components, the mechanisms in TOSCs are complex. Multiple models for those mechanisms currently exist, which differ mainly in the description of the composition dependence of the open-circuit voltage. However, these models are not defined precisely, they are based on narrow presuppositions and they frequently contradict each other. Moreover, although the state of knowledge has evolved since the development of models, new TOSCs are still assigned to them. This Review describes the existing models and concepts, highlights their inconsistencies and summarizes newer results on electronic and morphological properties of TOSCs. Subsequently, the conventional models are revisited in the light of these new insights, with the aim of pointing out existing gaps and providing the stimulus for challenging old concepts.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In ternary organic solar cells (TOSCs), three different components are mixed to form the photoactive layer, opening up opportunities to boost the power conversion efficiency — for example, by broadening the absorption range, improving the blend morphology or tuning the exciton splitting and charge extraction. Because of these possibilities, ternary systems are among the best performing OSCs and will have a crucial role in the future of organic photovoltaics. Owing to the interplay of three different components, the mechanisms in TOSCs are complex. Multiple models for those mechanisms currently exist, which differ mainly in the description of the composition dependence of the open-circuit voltage. However, these models are not defined precisely, they are based on narrow presuppositions and they frequently contradict each other. Moreover, although the state of knowledge has evolved since the development of models, new TOSCs are still assigned to them. This Review describes the existing models and concepts, highlights their inconsistencies and summarizes newer results on electronic and morphological properties of TOSCs. Subsequently, the conventional models are revisited in the light of these new insights, with the aim of pointing out existing gaps and providing the stimulus for challenging old concepts.
14.
A Semerci, A Buyruk, S Emin, R Hooijer, D Kovacheva, P Mayer, M A Reus, D Blätte, M Günther, N F Hartmann, S Lotfi, J P Hofmann, P Müller-Buschbaum, T Bein, T Ameri
In: Advanced Optical Materials, vol. 11, no. 16, pp. 2300267, 2023, ISSN: 2195-1071.
@article{nokey,
title = {A Novel Multi-Functional Thiophene-Based Organic Cation as Passivation, Crystalline Orientation, and Organic Spacer Agent for Low-Dimensional 3D/1D Perovskite Solar Cells},
author = {A Semerci and A Buyruk and S Emin and R Hooijer and D Kovacheva and P Mayer and M A Reus and D Bl\"{a}tte and M G\"{u}nther and N F Hartmann and S Lotfi and J P Hofmann and P M\"{u}ller-Buschbaum and T Bein and T Ameri},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adom.202300267},
doi = {https://doi.org/10.1002/adom.202300267},
issn = {2195-1071},
year = {2023},
date = {2023-05-25},
journal = {Advanced Optical Materials},
volume = {11},
number = {16},
pages = {2300267},
abstract = {Abstract Recently, the mixed-dimensional (3D/2D or 3D/1D) perovskite solar cells using small organic spacers have attracted interest due to their outstanding long-term stability. Here, a new type of thiophene-based organic cation 2-(thiophene-2yl-)pyridine-1-ium iodide (ThPyI), which is used to fabricate mixed-dimensional 3D/1D perovskite solar cells, is presented. The ThPyI-based 1D perovskitoid is applied as a passivator on top of a 3D methyl ammonium lead iodide (MAPI) to fabricate surface-passivated 3D/1D perovskite films or added alone into the 3D perovskite precursor to generate bulk-passivated 3D MAPI. The 1D perovskitoid acts as a passivating agent at the grain boundaries of surface-passivated 3D/1D, which improves the power conversion efficiency (PCE) of the solar cells. Grazing incidence wide-angle X-ray scattering (GIWAXS) studies confirm that ThPyI triggers the preferential orientation of the bulk MAPI slabs, which is essential to enhance charge transport. Champion bulk-passivated 3D and surface-passivated 3D/1D devices yield 14.10% and 19.60% PCE, respectively. The bulk-passivated 3D offers favorable stability, with 84% PCE retained after 2000 h without encapsulation. This study brings a new perspective to the design of organic spacers having a different binding motif and a passivation strategy to mitigate the impact of defects in hybrid 3D/1D perovskite solar cells.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Abstract Recently, the mixed-dimensional (3D/2D or 3D/1D) perovskite solar cells using small organic spacers have attracted interest due to their outstanding long-term stability. Here, a new type of thiophene-based organic cation 2-(thiophene-2yl-)pyridine-1-ium iodide (ThPyI), which is used to fabricate mixed-dimensional 3D/1D perovskite solar cells, is presented. The ThPyI-based 1D perovskitoid is applied as a passivator on top of a 3D methyl ammonium lead iodide (MAPI) to fabricate surface-passivated 3D/1D perovskite films or added alone into the 3D perovskite precursor to generate bulk-passivated 3D MAPI. The 1D perovskitoid acts as a passivating agent at the grain boundaries of surface-passivated 3D/1D, which improves the power conversion efficiency (PCE) of the solar cells. Grazing incidence wide-angle X-ray scattering (GIWAXS) studies confirm that ThPyI triggers the preferential orientation of the bulk MAPI slabs, which is essential to enhance charge transport. Champion bulk-passivated 3D and surface-passivated 3D/1D devices yield 14.10% and 19.60% PCE, respectively. The bulk-passivated 3D offers favorable stability, with 84% PCE retained after 2000 h without encapsulation. This study brings a new perspective to the design of organic spacers having a different binding motif and a passivation strategy to mitigate the impact of defects in hybrid 3D/1D perovskite solar cells.
13.
M Günther, S Lotfi, S S Rivas, D Blätte, J P Hofmann, T Bein, T Ameri
The neglected influence of zinc oxide light-soaking on stability measurements of inverted organic solar cells Journal Article
In: Advanced Functional Materials, vol. 33, no. 13, pp. 2209768, 2023, ISSN: 1616-301X.
@article{nokey,
title = {The neglected influence of zinc oxide light-soaking on stability measurements of inverted organic solar cells},
author = {M G\"{u}nther and S Lotfi and S S Rivas and D Bl\"{a}tte and J P Hofmann and T Bein and T Ameri},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202209768},
doi = {https://doi.org/10.1002/adfm.202209768},
issn = {1616-301X},
year = {2023},
date = {2023-01-15},
journal = {Advanced Functional Materials},
volume = {33},
number = {13},
pages = {2209768},
abstract = {Abstract Although zinc oxide (ZnO) is one of the most commonly used materials for electron transport layers in organic solar cells (OSCs), it also comes with disadvantages such as the so-called light-soaking issues, i.e., its need for exposure to UV light to reach its full potential in OSCs. Here, the impact of ZnO light-soaking issues on stability measurements of OSCs is investigated. It is found that in the absence of UV light a reversible degradation occurs, which is independent of the used active layer material and accelerates at higher temperatures but can be undone with a short UV exposure. This reversible aging is attributed to the re-adsorption of oxygen, which for manufacturing reasons is trapped at the interface of ZnO, even in an oxygen-free environment. This oxygen can be removed with a UV pretreatment of the ZnO but at the expense of device efficiency and production that has to take place in an oxygen-free environment. This study establishes that stability measurements of ZnO-containing OSCs must be performed exclusively with a light source including a UV part since the usage of a simple white light source \textendash as often reported in the literature \textendash can lead to erroneous results.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Abstract Although zinc oxide (ZnO) is one of the most commonly used materials for electron transport layers in organic solar cells (OSCs), it also comes with disadvantages such as the so-called light-soaking issues, i.e., its need for exposure to UV light to reach its full potential in OSCs. Here, the impact of ZnO light-soaking issues on stability measurements of OSCs is investigated. It is found that in the absence of UV light a reversible degradation occurs, which is independent of the used active layer material and accelerates at higher temperatures but can be undone with a short UV exposure. This reversible aging is attributed to the re-adsorption of oxygen, which for manufacturing reasons is trapped at the interface of ZnO, even in an oxygen-free environment. This oxygen can be removed with a UV pretreatment of the ZnO but at the expense of device efficiency and production that has to take place in an oxygen-free environment. This study establishes that stability measurements of ZnO-containing OSCs must be performed exclusively with a light source including a UV part since the usage of a simple white light source – as often reported in the literature – can lead to erroneous results.
12.
M Shadabfar, M Ehsani, H A Khonakdar, M Abdouss, T Ameri
Waterborne conductive carbon paste with an eco-friendly binder Journal Article
In: Cellulose, 2022, ISSN: 1572-882X.
@article{nokey,
title = {Waterborne conductive carbon paste with an eco-friendly binder},
author = {M Shadabfar and M Ehsani and H A Khonakdar and M Abdouss and T Ameri},
url = {https://doi.org/10.1007/s10570-022-04998-5},
doi = {10.1007/s10570-022-04998-5},
issn = {1572-882X},
year = {2022},
date = {2022-12-22},
journal = {Cellulose},
abstract = {Conductive carbon pastes are widely used in flexible and printed electronic devices such as wearable electronics and optoelectronics. The use of conductive pastes comes with some challenges, such as replacing toxic synthetic materials with environmentally-friendly and sustainable ones, achieving an appropriate level of electrical conductivity, and controlling the thickness of the coated film. Waterborne conductive carbon pastes have been used to tackle the mentioned problems. In this study, carboxymethyl cellulose (CMC) was introduced as an eco-friendly binder combined with Graphene Nanoplatelets (GNPs) and Carbon Nanotubes (CNTs) to synthesize a conductive carbon paste without any metallic elements. The double-coated GNP/CNT/CMC paste films were coated on a paper surface using the doctor blade method. Morphological and thermal characteristics, sheet resistance, and optoelectrical properties of the paste films were comprehensively investigated. It was found that the conductive carbon paste containing 35 wt% CNTs exhibits higher conductivity (80.4 S/m) than the other combinations. Moreover, Field Emission Scanning Electron Microscopy (FE-SEM) showed that GNPs and CNTs are distributed within cellulosic matrix very homogeneously. Great flexibility and high electrical conductivity are achieved in the paste film. EIS results implied that the double-coated paste could act as a highly conductive surface in fabricating electrochemical sensors with high performance. In conclusion, this study represents a novel and environmentally-friendly method to produce low-cost, highly-efficient, and large-scale conductive carbon paste.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Conductive carbon pastes are widely used in flexible and printed electronic devices such as wearable electronics and optoelectronics. The use of conductive pastes comes with some challenges, such as replacing toxic synthetic materials with environmentally-friendly and sustainable ones, achieving an appropriate level of electrical conductivity, and controlling the thickness of the coated film. Waterborne conductive carbon pastes have been used to tackle the mentioned problems. In this study, carboxymethyl cellulose (CMC) was introduced as an eco-friendly binder combined with Graphene Nanoplatelets (GNPs) and Carbon Nanotubes (CNTs) to synthesize a conductive carbon paste without any metallic elements. The double-coated GNP/CNT/CMC paste films were coated on a paper surface using the doctor blade method. Morphological and thermal characteristics, sheet resistance, and optoelectrical properties of the paste films were comprehensively investigated. It was found that the conductive carbon paste containing 35 wt% CNTs exhibits higher conductivity (80.4 S/m) than the other combinations. Moreover, Field Emission Scanning Electron Microscopy (FE-SEM) showed that GNPs and CNTs are distributed within cellulosic matrix very homogeneously. Great flexibility and high electrical conductivity are achieved in the paste film. EIS results implied that the double-coated paste could act as a highly conductive surface in fabricating electrochemical sensors with high performance. In conclusion, this study represents a novel and environmentally-friendly method to produce low-cost, highly-efficient, and large-scale conductive carbon paste.
11.
E Khorshidi, B Rezaei, A Kavousighahfarokhi, J Hanisch, M A Reus, P Müller-Buschbaum, T Ameri
In: ACS Applied Materials & Interfaces, vol. 14, no. 49, pp. 54623-54634, 2022, ISSN: 1944-8244.
@article{nokey,
title = {Antisolvent Additive Engineering for Boosting Performance and Stability of Graded Heterojunction Perovskite Solar Cells Using Amide-Functionalized Graphene Quantum Dots},
author = {E Khorshidi and B Rezaei and A Kavousighahfarokhi and J Hanisch and M A Reus and P M\"{u}ller-Buschbaum and T Ameri},
url = {https://doi.org/10.1021/acsami.2c12944},
doi = {10.1021/acsami.2c12944},
issn = {1944-8244},
year = {2022},
date = {2022-11-29},
journal = {ACS Applied Materials \& Interfaces},
volume = {14},
number = {49},
pages = {54623-54634},
abstract = {Additive and antisolvent engineering strategies are outstandingly efficient in enhancing perovskite quality, photovoltaic performance, and stability of perovskite solar cells (PSCs). In this work, an effective approach is applied by coupling the antisolvent mixture and multi-functional additive procedures, which is recognized as antisolvent additive engineering (AAE). The graphene quantum dots functionalized with amide (AGQDs), which consists of carbonyl, amine, and long hydrophobic alkyl chain functional groups, are added to the antisolvent mixture of toluene (T) and hexane (H) as an efficient additive to form the CH3NH3PbI3 (MAPI):AGQDs graded heterojunction structure. A broad range of analytical techniques, including scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, space charge limited current, UV\textendashvisible spectroscopy, external quantum efficiency, and time-of-flight secondary ion mass spectrometry, are used to investigate the effect of AAE treatment with AGQDs on the quality of perovskite film and performance of the PSCs. Importantly, not only a uniform and dense perovskite film with hydrophobic property is obtained but also defects on the perovskite surface are significantly passivated by the interaction between AGQDs and uncoordinated Pb2+. As a result, an enhanced power conversion efficiency (PCE) of 19.10% is achieved for the champion PSCs treated with AGQD additive, compared to the PCE of 16.00% for untreated reference PSCs. In addition, the high-efficiency PSCs based on AGQDs show high stability and maintain 89% of their initial PCE after 960 h in ambient conditions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Additive and antisolvent engineering strategies are outstandingly efficient in enhancing perovskite quality, photovoltaic performance, and stability of perovskite solar cells (PSCs). In this work, an effective approach is applied by coupling the antisolvent mixture and multi-functional additive procedures, which is recognized as antisolvent additive engineering (AAE). The graphene quantum dots functionalized with amide (AGQDs), which consists of carbonyl, amine, and long hydrophobic alkyl chain functional groups, are added to the antisolvent mixture of toluene (T) and hexane (H) as an efficient additive to form the CH3NH3PbI3 (MAPI):AGQDs graded heterojunction structure. A broad range of analytical techniques, including scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, space charge limited current, UV–visible spectroscopy, external quantum efficiency, and time-of-flight secondary ion mass spectrometry, are used to investigate the effect of AAE treatment with AGQDs on the quality of perovskite film and performance of the PSCs. Importantly, not only a uniform and dense perovskite film with hydrophobic property is obtained but also defects on the perovskite surface are significantly passivated by the interaction between AGQDs and uncoordinated Pb2+. As a result, an enhanced power conversion efficiency (PCE) of 19.10% is achieved for the champion PSCs treated with AGQD additive, compared to the PCE of 16.00% for untreated reference PSCs. In addition, the high-efficiency PSCs based on AGQDs show high stability and maintain 89% of their initial PCE after 960 h in ambient conditions.
10.
E Khorshidi, B Rezaei, D Blätte, A Buyruk, M A Reus, J Hanisch, B Böller, P Müller-Buschbaum, T Ameri
Hydrophobic Graphene Quantum Dots for Defect Passivation and Enhanced Moisture Stability of CH3NH3PbI3 Perovskite Solar Cells Journal Article
In: Solar RRL, vol. n/a, no. n/a, pp. 2200023, 2022, ISSN: 2367-198X.
@article{nokey,
title = {Hydrophobic Graphene Quantum Dots for Defect Passivation and Enhanced Moisture Stability of CH3NH3PbI3 Perovskite Solar Cells},
author = {E Khorshidi and B Rezaei and D Bl\"{a}tte and A Buyruk and M A Reus and J Hanisch and B B\"{o}ller and P M\"{u}ller-Buschbaum and T Ameri},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/solr.202200023},
doi = {https://doi.org/10.1002/solr.202200023},
issn = {2367-198X},
year = {2022},
date = {2022-03-19},
journal = {Solar RRL},
volume = {n/a},
number = {n/a},
pages = {2200023},
abstract = {Passivating the defects and grain boundaries (GBs) of perovskite films at the interface by interface engineering is a promising route to achieve efficient and stable perovskite solar cells (PSCs). Herein, a new type of graphene, that is, hydrophobic graphene quantum dots (HGQDs) containing amide linkages, which consist of carbonyl and dodecyl amine groups, is successfully used as a bifunctional interface modifier to engineer the interface of the perovskite/hole transport layer. A comprehensive characterization including X-ray photoelectron spectroscopy, Fourier-transform photocurrent spectroscopy, Raman spectroscopy, photoluminescence spectroscopy, and space-charge-limited current measurements is performed to identify the underlying passivation mechanisms. It can be demonstrated that the HGQDs, due to the bifunctional groups containing N and O atoms, effectively passivate the uncoordinated Pb2+ ions at the perovskite film surface and GBs and consequently induce a lower trap state density. Moreover, HGQDs enhance the quality of the perovskite film which reduces the charge recombination at the interface. Therefore, the power conversion efficiency of PSCs treated with HGQDs is significantly increased from 16.00% to 18.30%, mainly based on the improved open-circuit voltage and fill factor. Importantly, the HGQDs featuring hydrophobicity due to alkyl chains significantly enhance moisture stability.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Passivating the defects and grain boundaries (GBs) of perovskite films at the interface by interface engineering is a promising route to achieve efficient and stable perovskite solar cells (PSCs). Herein, a new type of graphene, that is, hydrophobic graphene quantum dots (HGQDs) containing amide linkages, which consist of carbonyl and dodecyl amine groups, is successfully used as a bifunctional interface modifier to engineer the interface of the perovskite/hole transport layer. A comprehensive characterization including X-ray photoelectron spectroscopy, Fourier-transform photocurrent spectroscopy, Raman spectroscopy, photoluminescence spectroscopy, and space-charge-limited current measurements is performed to identify the underlying passivation mechanisms. It can be demonstrated that the HGQDs, due to the bifunctional groups containing N and O atoms, effectively passivate the uncoordinated Pb2+ ions at the perovskite film surface and GBs and consequently induce a lower trap state density. Moreover, HGQDs enhance the quality of the perovskite film which reduces the charge recombination at the interface. Therefore, the power conversion efficiency of PSCs treated with HGQDs is significantly increased from 16.00% to 18.30%, mainly based on the improved open-circuit voltage and fill factor. Importantly, the HGQDs featuring hydrophobicity due to alkyl chains significantly enhance moisture stability.
9.
S Grott, A Kotobi, L K Reb, C L Weindl, R Guo, S Yin, K S Wienhold, W Chen, T Ameri, M Schwartzkopf, S V Roth, P Müller-Buschbaum
Solvent Tuning of the Active Layer Morphology of Non-Fullerene Based Organic Solar Cells Journal Article
In: Solar RRL, vol. n/a, no. n/a, pp. 2101084, 2022, ISSN: 2367-198X.
@article{nokey,
title = {Solvent Tuning of the Active Layer Morphology of Non-Fullerene Based Organic Solar Cells},
author = {S Grott and A Kotobi and L K Reb and C L Weindl and R Guo and S Yin and K S Wienhold and W Chen and T Ameri and M Schwartzkopf and S V Roth and P M\"{u}ller-Buschbaum},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/solr.202101084},
doi = {https://doi.org/10.1002/solr.202101084},
issn = {2367-198X},
year = {2022},
date = {2022-02-12},
journal = {Solar RRL},
volume = {n/a},
number = {n/a},
pages = {2101084},
abstract = {Non-fullerene acceptor (NFA)-based organic solar cells have made tremendous progress in recent years. For the neat NFA system PBDB-T:ITIC, the film morphology and crystallinity are tailored by the choice of the solvent used for spin coating the active layers. Three different chlorinated solvents, chlorobenzene (CB), chloroform, and dichlorobenzene, are compared and the obtained active layer morphology is correlated with the optoelectronic properties and the device performance. The small domain sizes in the case of CB are most beneficial for the device performance, whereas the largest number or size of face-on PBDB-T crystallites is not causing the highest power conversion efficiencies (PCEs). In addition, when using CB, the number of edge-on crystallites is highest and the distances between neighboring domains are small. The smoothest blend films are realized with CB, which exhibit correlated roughness with their substrates and no large aggregates have formed in these blend films. Thus, CB offers the best way to balance the aggregation and crystallization kinetics in the active layer and enables the highest PCE values.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Non-fullerene acceptor (NFA)-based organic solar cells have made tremendous progress in recent years. For the neat NFA system PBDB-T:ITIC, the film morphology and crystallinity are tailored by the choice of the solvent used for spin coating the active layers. Three different chlorinated solvents, chlorobenzene (CB), chloroform, and dichlorobenzene, are compared and the obtained active layer morphology is correlated with the optoelectronic properties and the device performance. The small domain sizes in the case of CB are most beneficial for the device performance, whereas the largest number or size of face-on PBDB-T crystallites is not causing the highest power conversion efficiencies (PCEs). In addition, when using CB, the number of edge-on crystallites is highest and the distances between neighboring domains are small. The smoothest blend films are realized with CB, which exhibit correlated roughness with their substrates and no large aggregates have formed in these blend films. Thus, CB offers the best way to balance the aggregation and crystallization kinetics in the active layer and enables the highest PCE values.
8.
Y Zou, S Yuan, A Buyruk, J Eichhorn, S Yin, M A Reus, T Xiao, S Pratap, S Liang, C L Weindl, W Chen, C Mu, I D Sharp, T Ameri, M Schwartzkopf, S V Roth, P Müller-Buschbaum
The Influence of CsBr on Crystal Orientation and Optoelectronic Properties of MAPbI3-Based Solar Cells Journal Article
In: ACS Applied Materials & Interfaces, vol. 14, pp. 2958, 2022, ISSN: 1944-8244.
@article{nokey,
title = {The Influence of CsBr on Crystal Orientation and Optoelectronic Properties of MAPbI3-Based Solar Cells},
author = {Y Zou and S Yuan and A Buyruk and J Eichhorn and S Yin and M A Reus and T Xiao and S Pratap and S Liang and C L Weindl and W Chen and C Mu and I D Sharp and T Ameri and M Schwartzkopf and S V Roth and P M\"{u}ller-Buschbaum},
url = {https://doi.org/10.1021/acsami.1c22184},
doi = {10.1021/acsami.1c22184},
issn = {1944-8244},
year = {2022},
date = {2022-01-06},
urldate = {2022-01-06},
journal = {ACS Applied Materials \& Interfaces},
volume = {14},
pages = {2958},
abstract = {Crystal orientations are closely related to the behavior of photogenerated charge carriers and are vital for controlling the optoelectronic properties of perovskite solar cells. Herein, we propose a facile approach to reveal the effect of lattice plane orientation distribution on the charge carrier kinetics via constructing CsBr-doped mixed cation perovskite phases. With grazing-incidence wide-angle X-ray scattering measurements, we investigate the crystallographic properties of mixed perovskite films at the microscopic scale and reveal the effect of the extrinsic CsBr doping on the stacking behavior of the lattice planes. Combined with transient photocurrent, transient photovoltage, and space-charge-limited current measurements, the transport dynamics and recombination of the photogenerated charge carriers are characterized. It is demonstrated that CsBr compositional engineering can significantly affect the perovskite crystal structure in terms of the orientation distribution of crystal planes and passivation of trap-state densities, as well as simultaneously facilitate the photogenerated charge carrier transport across the absorber and its interfaces. This strategy provides unique insight into the underlying relationship between the stacking pattern of crystal planes, photogenerated charge carrier transport, and optoelectronic properties of solar cells.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Crystal orientations are closely related to the behavior of photogenerated charge carriers and are vital for controlling the optoelectronic properties of perovskite solar cells. Herein, we propose a facile approach to reveal the effect of lattice plane orientation distribution on the charge carrier kinetics via constructing CsBr-doped mixed cation perovskite phases. With grazing-incidence wide-angle X-ray scattering measurements, we investigate the crystallographic properties of mixed perovskite films at the microscopic scale and reveal the effect of the extrinsic CsBr doping on the stacking behavior of the lattice planes. Combined with transient photocurrent, transient photovoltage, and space-charge-limited current measurements, the transport dynamics and recombination of the photogenerated charge carriers are characterized. It is demonstrated that CsBr compositional engineering can significantly affect the perovskite crystal structure in terms of the orientation distribution of crystal planes and passivation of trap-state densities, as well as simultaneously facilitate the photogenerated charge carrier transport across the absorber and its interfaces. This strategy provides unique insight into the underlying relationship between the stacking pattern of crystal planes, photogenerated charge carrier transport, and optoelectronic properties of solar cells.
7.
T Ameri, L Ke, N Gasparini, R Soltani, M Günther, A Buyruk, A A Amin
Advanced Printed Semiconductors for Energy and Electronic Applications Journal Article
In: Video Proceedings of Advanced Materials, vol. 2, 2021.
@article{nokey,
title = {Advanced Printed Semiconductors for Energy and Electronic Applications},
author = {T Ameri and L Ke and N Gasparini and R Soltani and M G\"{u}nther and A Buyruk and A A Amin},
url = {https://www.proceedings.iaamonline.org/image/article/1628028399Tayebeh-Ameri---Abstract.pdf},
doi = {https://www.proceedings.iaamonline.org/image/article/1628028399Tayebeh-Ameri---Abstract.pdf},
year = {2021},
date = {2021-08-03},
urldate = {2021-08-03},
journal = {Video Proceedings of Advanced Materials},
volume = {2},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
6.
A Buyruk, D Blätte, M Günther, M A Scheel, N F Hartmann, M Döblinger, A Weis, A Hartschuh, P Müller-Buschbaum, T Bein, T Ameri
1,10-Phenanthroline as an Efficient Bifunctional Passivating Agent for MAPbI3 Perovskite Solar Cells Journal Article
In: ACS Applied Materials & Interfaces, 2021, ISSN: 1944-8244.
@article{,
title = {1,10-Phenanthroline as an Efficient Bifunctional Passivating Agent for MAPbI3 Perovskite Solar Cells},
author = {A Buyruk and D Bl\"{a}tte and M G\"{u}nther and M A Scheel and N F Hartmann and M D\"{o}blinger and A Weis and A Hartschuh and P M\"{u}ller-Buschbaum and T Bein and T Ameri},
url = {https://doi.org/10.1021/acsami.1c05055},
doi = {10.1021/acsami.1c05055},
issn = {1944-8244},
year = {2021},
date = {2021-07-09},
urldate = {2021-07-09},
journal = {ACS Applied Materials \& Interfaces},
abstract = {Passivation is one of the most promising concepts to heal defects created at the surface and grain boundaries of polycrystalline perovskite thin films, which significantly deteriorate the photovoltaic performance and stability of corresponding devices. Here, 1,10-phenanthroline, known as a bidentate chelating ligand, is implemented between the methylammonium lead iodide (MAPbI3) film and the hole-transport layer for both passivating the lead-based surface defects (undercoordinated lead ions) and converting the excess/unreacted lead iodide (PbI2) buried at interfaces, which is problematic for the long-term stability, into “neutralized” and beneficial species (PbI2(1,10-phen)x},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Passivation is one of the most promising concepts to heal defects created at the surface and grain boundaries of polycrystalline perovskite thin films, which significantly deteriorate the photovoltaic performance and stability of corresponding devices. Here, 1,10-phenanthroline, known as a bidentate chelating ligand, is implemented between the methylammonium lead iodide (MAPbI3) film and the hole-transport layer for both passivating the lead-based surface defects (undercoordinated lead ions) and converting the excess/unreacted lead iodide (PbI2) buried at interfaces, which is problematic for the long-term stability, into “neutralized” and beneficial species (PbI2(1,10-phen)x
5.
N Li, R Guo, W Chen, V Körstgens, J E Heger, S Liang, C J Brett, M A Hossain, J Zheng, P S Deimel, A Buyruk, F Allegretti, M Schwartzkopf, J G C Veinot, G Schmitz, J V Barth, T Ameri, S V Roth, P Müller-Buschbaum
In: Advanced Functional Materials, vol. 31, iss. 34, pp. 2102105, 2021, ISSN: 1616-301X.
@article{,
title = {Tailoring Ordered Mesoporous Titania Films via Introducing Germanium Nanocrystals for Enhanced Electron Transfer Photoanodes for Photovoltaic Applications},
author = {N Li and R Guo and W Chen and V K\"{o}rstgens and J E Heger and S Liang and C J Brett and M A Hossain and J Zheng and P S Deimel and A Buyruk and F Allegretti and M Schwartzkopf and J G C Veinot and G Schmitz and J V Barth and T Ameri and S V Roth and P M\"{u}ller-Buschbaum},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202102105},
doi = {https://doi.org/10.1002/adfm.202102105},
issn = {1616-301X},
year = {2021},
date = {2021-06-17},
urldate = {2021-06-17},
journal = {Advanced Functional Materials},
volume = {31},
issue = {34},
pages = {2102105},
abstract = {Abstract Based on a diblock-copolymer templated sol\textendashgel synthesis, germanium nanocrystals (GeNCs) are introduced to tailor mesoporous titania (TiO2) films for obtaining more efficient anodes for photovoltaic applications. After thermal annealing in air, the hybrid films with different GeNC content are investigated and compared with films undergoing an argon atmosphere annealing. The surface and inner morphologies of the TiO2/GeOx nanocomposite films are probed via scanning electron microscopy and grazing-incidence small-angle X-ray scattering. The crystal phase, chemical composition, and optical properties of the nanocomposite films are examined with transmission electron microscopy, X-ray photoelectron spectroscopy, and ultraviolet\textendashvisible spectroscopy. Special focus is set on the air-annealed nanocomposite films since they hold greater promise for photovoltaics. Specifically, the charge\textendashcarrier dynamics of these air-annealed nanocomposite films are studied, and it is found that, compared with pristine TiO2 photoanodes, the GeNC addition enhances the electron transfer, yielding an increase in the short-circuit photocurrent density of exemplary perovskite solar cells and thus, an enhanced device efficiency as well as a significantly reduced hysteresis.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Abstract Based on a diblock-copolymer templated sol–gel synthesis, germanium nanocrystals (GeNCs) are introduced to tailor mesoporous titania (TiO2) films for obtaining more efficient anodes for photovoltaic applications. After thermal annealing in air, the hybrid films with different GeNC content are investigated and compared with films undergoing an argon atmosphere annealing. The surface and inner morphologies of the TiO2/GeOx nanocomposite films are probed via scanning electron microscopy and grazing-incidence small-angle X-ray scattering. The crystal phase, chemical composition, and optical properties of the nanocomposite films are examined with transmission electron microscopy, X-ray photoelectron spectroscopy, and ultraviolet–visible spectroscopy. Special focus is set on the air-annealed nanocomposite films since they hold greater promise for photovoltaics. Specifically, the charge–carrier dynamics of these air-annealed nanocomposite films are studied, and it is found that, compared with pristine TiO2 photoanodes, the GeNC addition enhances the electron transfer, yielding an increase in the short-circuit photocurrent density of exemplary perovskite solar cells and thus, an enhanced device efficiency as well as a significantly reduced hysteresis.
4.
M Günther, D Blätte, A L Oechsle, S S Rivas, Yousefi A A Amin, P Müller-Buschbaum, T Bein, T Ameri
Increasing Photostability of Inverted Nonfullerene Organic Solar Cells by Using Fullerene Derivative Additives Journal Article
In: ACS Applied Materials & Interfaces, 2021, ISSN: 1944-8244.
@article{,
title = {Increasing Photostability of Inverted Nonfullerene Organic Solar Cells by Using Fullerene Derivative Additives},
author = {M G\"{u}nther and D Bl\"{a}tte and A L Oechsle and S S Rivas and Yousefi A A Amin and P M\"{u}ller-Buschbaum and T Bein and T Ameri},
url = {https://doi.org/10.1021/acsami.1c00700},
doi = {10.1021/acsami.1c00700},
issn = {1944-8244},
year = {2021},
date = {2021-04-16},
urldate = {2021-04-16},
journal = {ACS Applied Materials \& Interfaces},
abstract = {Organic solar cells (OSCs) recently achieved efficiencies of over 18% and are well on their way to practical applications, but still considerable stability issues need to be overcome. One major problem emerges from the electron transport material zinc oxide (ZnO), which is mainly used in the inverted device architecture and decomposes many high-performance nonfullerene acceptors due to its photocatalytic activity. In this work, we add three different fullerene derivatives\textemdashPC71BM, ICMA, and BisPCBM\textemdashto an inverted binary PBDB-TF:IT-4F system in order to suppress the photocatalytic degradation of IT-4F on ZnO via the radical scavenging abilities of the fullerenes. We demonstrate that the addition of 5% fullerene not only increases the performance of the binary PBDB-TF:IT-4F system but also significantly improves the device lifetime under UV illumination in an inert atmosphere. While the binary devices lose 20% of their initial efficiency after only 3 h, this time is increased fivefold for the most promising ternary devices with ICMA. We attribute this improvement to a reduced photocatalytic decomposition of IT-4F in the ternary system, which results in a decreased recombination. We propose that the added fullerenes protect the IT-4F by acting as a sacrificial reagent, thereby suppressing the trap state formation. Furthermore, we show that the protective effect of the most promising fullerene ICMA is transferable to two other binary systems PBDB-TF:BTP-4F and PTB7-Th:IT-4F. Importantly, this effect can also increase the air stability of PBDB-TF:IT-4F. This work demonstrates that the addition of fullerene derivatives is a transferable and straightforward strategy to improve the stability of OSCs.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Organic solar cells (OSCs) recently achieved efficiencies of over 18% and are well on their way to practical applications, but still considerable stability issues need to be overcome. One major problem emerges from the electron transport material zinc oxide (ZnO), which is mainly used in the inverted device architecture and decomposes many high-performance nonfullerene acceptors due to its photocatalytic activity. In this work, we add three different fullerene derivatives—PC71BM, ICMA, and BisPCBM—to an inverted binary PBDB-TF:IT-4F system in order to suppress the photocatalytic degradation of IT-4F on ZnO via the radical scavenging abilities of the fullerenes. We demonstrate that the addition of 5% fullerene not only increases the performance of the binary PBDB-TF:IT-4F system but also significantly improves the device lifetime under UV illumination in an inert atmosphere. While the binary devices lose 20% of their initial efficiency after only 3 h, this time is increased fivefold for the most promising ternary devices with ICMA. We attribute this improvement to a reduced photocatalytic decomposition of IT-4F in the ternary system, which results in a decreased recombination. We propose that the added fullerenes protect the IT-4F by acting as a sacrificial reagent, thereby suppressing the trap state formation. Furthermore, we show that the protective effect of the most promising fullerene ICMA is transferable to two other binary systems PBDB-TF:BTP-4F and PTB7-Th:IT-4F. Importantly, this effect can also increase the air stability of PBDB-TF:IT-4F. This work demonstrates that the addition of fullerene derivatives is a transferable and straightforward strategy to improve the stability of OSCs.
3.
S Wang, Yousefi A A Amin, L Wu, M Cao, Q Zhang, T Ameri
Perovskite Nanocrystals: Synthesis, Stability, and Optoelectronic Applications Journal Article
In: Small Structures, vol. n/a, no. n/a, pp. 2000124, 2021, ISSN: 2688-4062.
@article{,
title = {Perovskite Nanocrystals: Synthesis, Stability, and Optoelectronic Applications},
author = {S Wang and Yousefi A A Amin and L Wu and M Cao and Q Zhang and T Ameri},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/sstr.202000124},
doi = {https://doi.org/10.1002/sstr.202000124},
issn = {2688-4062},
year = {2021},
date = {2021-02-07},
journal = {Small Structures},
volume = {n/a},
number = {n/a},
pages = {2000124},
abstract = {Metal halide perovskite (MHP) materials, named as the game changers, have attracted researchers’ attention worldwide for over a decade. Among them, nanometer-scale perovskite nanocrystals (PNCs) have exhibited attractive photophysical properties, such as tunable bandgaps, narrow emission, strong light-absorption coefficients, and high defect tolerance, because they combined the excellent optoelectronic properties of bulk perovskite materials with strong quantum confinement effects of the nanoscale. These materials possess a great potential to be applied in the optoelectronic devices. For commercial applications in devices like solar cells (SCs), light-emitting diodes (LEDs), and photodetectors (PDs), the stability of PNCs against ambient atmosphere like oxygen and moisture, as well as light and high temperature is crucial. Herein, the synthetic methods and stability issues of the PNCs are introduced first, followed by the introduction of the strategies for improving their stability by encapsulation. The applications of PNCs in various optoelectronic devices are then briefly presented. Finally, the remained challenges in improving the stability of PNCs toward the PNC-based optoelectronics with high performance and great durability are addressed.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Metal halide perovskite (MHP) materials, named as the game changers, have attracted researchers’ attention worldwide for over a decade. Among them, nanometer-scale perovskite nanocrystals (PNCs) have exhibited attractive photophysical properties, such as tunable bandgaps, narrow emission, strong light-absorption coefficients, and high defect tolerance, because they combined the excellent optoelectronic properties of bulk perovskite materials with strong quantum confinement effects of the nanoscale. These materials possess a great potential to be applied in the optoelectronic devices. For commercial applications in devices like solar cells (SCs), light-emitting diodes (LEDs), and photodetectors (PDs), the stability of PNCs against ambient atmosphere like oxygen and moisture, as well as light and high temperature is crucial. Herein, the synthetic methods and stability issues of the PNCs are introduced first, followed by the introduction of the strategies for improving their stability by encapsulation. The applications of PNCs in various optoelectronic devices are then briefly presented. Finally, the remained challenges in improving the stability of PNCs toward the PNC-based optoelectronics with high performance and great durability are addressed.
2.
Y Zou, R Guo, A Buyruk, W Chen, T Xiao, S Yin, X Jiang, L P Kreuzer, C Mu, T Ameri, M Schwartzkopf, S V Roth, P Müller-Buschbaum
Sodium Dodecylbenzene Sulfonate Interface Modification of Methylammonium Lead Iodide for Surface Passivation of Perovskite Solar Cells Journal Article
In: ACS Applied Materials & Interfaces, vol. 12, no. 47, pp. 52643-52651, 2020, ISSN: 1944-8244.
@article{nokey,
title = {Sodium Dodecylbenzene Sulfonate Interface Modification of Methylammonium Lead Iodide for Surface Passivation of Perovskite Solar Cells},
author = {Y Zou and R Guo and A Buyruk and W Chen and T Xiao and S Yin and X Jiang and L P Kreuzer and C Mu and T Ameri and M Schwartzkopf and S V Roth and P M\"{u}ller-Buschbaum},
url = {https://doi.org/10.1021/acsami.0c14732},
doi = {10.1021/acsami.0c14732},
issn = {1944-8244},
year = {2020},
date = {2020-11-15},
journal = {ACS Applied Materials \& Interfaces},
volume = {12},
number = {47},
pages = {52643-52651},
abstract = {Perovskite solar cells (PSCs) have been developed as a promising photovoltaic technology because of their excellent photovoltaic performance. However, interfacial recombination and charge carrier transport losses at the surface greatly limit the performance and stability of PSCs. In this work, the fabrication of high-quality PSCs based on methylammonium lead iodide with excellent ambient stability is reported. An anionic surfactant, sodium dodecylbenzene sulfonate (SDBS), is introduced to simultaneously passivate the defect states and stabilize the cubic phase of the perovskite film. The SDBS located at grain boundaries and the surface of the active layer can effectively passivate under-coordinated lead ions and protect the perovskite components from water-induced degradation. As a result, a champion power conversion efficiency (PCE) of 19.42% is achieved with an open-circuit voltage (VOC) of 1.12 V, a short-circuit current (JSC) of 23.23 mA cm\textendash2, and a fill factor (FF) of 74% in combination with superior moisture stability. The SDBS-passivated devices retain 80% of their initial average PCE after 2112 h of storage under ambient conditions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Perovskite solar cells (PSCs) have been developed as a promising photovoltaic technology because of their excellent photovoltaic performance. However, interfacial recombination and charge carrier transport losses at the surface greatly limit the performance and stability of PSCs. In this work, the fabrication of high-quality PSCs based on methylammonium lead iodide with excellent ambient stability is reported. An anionic surfactant, sodium dodecylbenzene sulfonate (SDBS), is introduced to simultaneously passivate the defect states and stabilize the cubic phase of the perovskite film. The SDBS located at grain boundaries and the surface of the active layer can effectively passivate under-coordinated lead ions and protect the perovskite components from water-induced degradation. As a result, a champion power conversion efficiency (PCE) of 19.42% is achieved with an open-circuit voltage (VOC) of 1.12 V, a short-circuit current (JSC) of 23.23 mA cm–2, and a fill factor (FF) of 74% in combination with superior moisture stability. The SDBS-passivated devices retain 80% of their initial average PCE after 2112 h of storage under ambient conditions.
1.
R Guo, A Buyruk, X Jiang, W Chen, L K Reb, M A Scheel, T Ameri, P Müller-Buschbaum
Tailoring the orientation of perovskite crystals via adding two-dimensional polymorphs for perovskite solar cells Journal Article
In: Journal of Physics: Energy, vol. 2, no. 3, pp. 034005, 2020, ISSN: 2515-7655.
@article{nokey,
title = {Tailoring the orientation of perovskite crystals via adding two-dimensional polymorphs for perovskite solar cells},
author = {R Guo and A Buyruk and X Jiang and W Chen and L K Reb and M A Scheel and T Ameri and P M\"{u}ller-Buschbaum},
url = {http://dx.doi.org/10.1088/2515-7655/ab90d0},
doi = {10.1088/2515-7655/ab90d0},
issn = {2515-7655},
year = {2020},
date = {2020-07-03},
urldate = {2020-07-03},
journal = {Journal of Physics: Energy},
volume = {2},
number = {3},
pages = {034005},
abstract = {Organic-inorganic perovskite materials are attracting increasing attention for their use in high-performance solar cells due to their outstanding properties, such as long diffusion lengths, low recombination rate, and tunable bandgap. Finding an effective method of defect passivation is thought to be a promising route for improvements toward narrowing the distribution of the power conversion efficiency (PCE) values, given by the spread in the PCE over different devices fabricated under identical conditions, for easier commercialization. In this work, we add 2‐(4‐fluoroph-enyl)ethyl ammonium iodide (p-f-PEAI) into the bulk of a mixed cation lead halide perovskite (CH3NH3PbBr3)0.15(HC(NH2)2PbI3)0.85 thin film. We investigate the influence of different p-f-PEAI concentrations on the optical properties, morphology, crystal orientation, charge carrier dynamics, and device performance. We observe that introducing the proper amount of p-f-PEAI changes the preferential orientation of the perovskite crystals, promotes the strength of the crystal textures, and suppresses non-radiative charge recombination. Thus, we obtain a narrower distribution of the PCE of perovskite solar cells (PSCs) without sacrificing the PCE values reached. This is an important step toward better reproducibility to realize the commercialization of PSCs.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Organic-inorganic perovskite materials are attracting increasing attention for their use in high-performance solar cells due to their outstanding properties, such as long diffusion lengths, low recombination rate, and tunable bandgap. Finding an effective method of defect passivation is thought to be a promising route for improvements toward narrowing the distribution of the power conversion efficiency (PCE) values, given by the spread in the PCE over different devices fabricated under identical conditions, for easier commercialization. In this work, we add 2‐(4‐fluoroph-enyl)ethyl ammonium iodide (p-f-PEAI) into the bulk of a mixed cation lead halide perovskite (CH3NH3PbBr3)0.15(HC(NH2)2PbI3)0.85 thin film. We investigate the influence of different p-f-PEAI concentrations on the optical properties, morphology, crystal orientation, charge carrier dynamics, and device performance. We observe that introducing the proper amount of p-f-PEAI changes the preferential orientation of the perovskite crystals, promotes the strength of the crystal textures, and suppresses non-radiative charge recombination. Thus, we obtain a narrower distribution of the PCE of perovskite solar cells (PSCs) without sacrificing the PCE values reached. This is an important step toward better reproducibility to realize the commercialization of PSCs.