Prof. Dr. Jacek Stolarczyk
Chair for Photonics and Optoelectronics
Department of Physics
LMU
Now: Jagiellonian University, Krakow
Academic Research Focus
- Photocatalysis
- Solar Light Harvesting
- Nanoparticle Interactions
- Controlled Self-assembly
- Solar Light Harvesting
- Nanoparticle Interactions
- Controlled Self-assembly
Fields of Application
Nanomaterials, Photo-(electro)catalysis, Photonics, Solar Cells / Photovoltaics
Publications
7.
J Fang, Y Wang, M Kurashvili, S Rieger, W Kasprzyk, Q Wang, J K Stolarczyk, J Feldmann, T Debnath
Simultaneous Hydrogen Generation and Exciplex Stimulated Emission in Photobasic Carbon Dots Journal Article
In: Angewandte Chemie International Edition, vol. 62, no. 33, pp. e202305817, 2023, ISSN: 1433-7851.
@article{nokey,
title = {Simultaneous Hydrogen Generation and Exciplex Stimulated Emission in Photobasic Carbon Dots},
author = {J Fang and Y Wang and M Kurashvili and S Rieger and W Kasprzyk and Q Wang and J K Stolarczyk and J Feldmann and T Debnath},
url = {https://doi.org/10.1002/anie.202305817},
doi = {https://doi.org/10.1002/anie.202305817},
issn = {1433-7851},
year = {2023},
date = {2023-08-14},
urldate = {2023-08-14},
journal = {Angewandte Chemie International Edition},
volume = {62},
number = {33},
pages = {e202305817},
abstract = {Abstract Photocatalytic water splitting is a promising approach to generating sustainable hydrogen. However, the transport of photoelectrons to the catalyst sites, usually within ps-to-ns timescales, is much faster than proton delivery (??s), which limits the activity. Therefore, the acceleration of abstraction of protons from water molecules towards the catalytic sites to keep up with the electron transfer rate can significantly promote hydrogen production. The photobasic effect that is the increase in proton affinity upon excitation offers means to achieve this objective. Herein, we design photobasic carbon dots and identify that internal pyridinic N sites are intrinsically photobasic. This is supported by steady-state and ultrafast spectroscopic measurements that demonstrate proton abstraction within a few picoseconds of excitation. Furthermore, we show that in water, they form a unique four-level lasing scheme with optical gain and stimulated emission. The latter competes with photocatalysis, revealing a rather unique mechanism for efficiency loss, such that the stimulated emission can act as a toggle for photocatalytic activity. This provides additional means of controlling the photocatalytic process and helps the rational design of photocatalytic materials.},
keywords = {},
pubstate = {published},
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Abstract Photocatalytic water splitting is a promising approach to generating sustainable hydrogen. However, the transport of photoelectrons to the catalyst sites, usually within ps-to-ns timescales, is much faster than proton delivery (??s), which limits the activity. Therefore, the acceleration of abstraction of protons from water molecules towards the catalytic sites to keep up with the electron transfer rate can significantly promote hydrogen production. The photobasic effect that is the increase in proton affinity upon excitation offers means to achieve this objective. Herein, we design photobasic carbon dots and identify that internal pyridinic N sites are intrinsically photobasic. This is supported by steady-state and ultrafast spectroscopic measurements that demonstrate proton abstraction within a few picoseconds of excitation. Furthermore, we show that in water, they form a unique four-level lasing scheme with optical gain and stimulated emission. The latter competes with photocatalysis, revealing a rather unique mechanism for efficiency loss, such that the stimulated emission can act as a toggle for photocatalytic activity. This provides additional means of controlling the photocatalytic process and helps the rational design of photocatalytic materials.
6.
Y Wang, E-P Yao, L Wu, J Feldmann, J K Stolarczyk
A Multi-Layer Device for Light-Triggered Hydrogen Production from Alkaline Methanol Journal Article
In: Angewandte Chemie International Edition, vol. 60, no. 51, pp. 26694-26701, 2021, ISSN: 1433-7851.
@article{nokey,
title = {A Multi-Layer Device for Light-Triggered Hydrogen Production from Alkaline Methanol},
author = {Y Wang and E-P Yao and L Wu and J Feldmann and J K Stolarczyk},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202109979},
doi = {https://doi.org/10.1002/anie.202109979},
issn = {1433-7851},
year = {2021},
date = {2021-10-13},
journal = {Angewandte Chemie International Edition},
volume = {60},
number = {51},
pages = {26694-26701},
abstract = {Abstract It usually requires high temperature and high pressure to reform methanol with water to hydrogen with high turnover frequency (TOF). Here we show that hydrogen can be produced from alkaline methanol on a light-triggered multi-layer system with a very high hydrogen evolution rate up to ca. 1 μmol s−1 under the illumination of a standard Pt-decorated carbon nitride. The system can achieve a remarkable TOF up to 1.8×106 moles of hydrogen per mole of Pt per hour under mild conditions. The total turnover number (TTN) of 470 000 measured over 38 hours is among the highest reported. The system does not lead to any COx emissions, hence it could feed clean hydrogen to fuel cells. In contrast to a slurry system, the proposed multi-layer system avoids particle aggregation and effectively uses light and Pt active sites. The performance is also attributed to the light-triggered reforming of alkaline methanol. This notable performance is a promising step toward practical light-driven hydrogen generation.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Abstract It usually requires high temperature and high pressure to reform methanol with water to hydrogen with high turnover frequency (TOF). Here we show that hydrogen can be produced from alkaline methanol on a light-triggered multi-layer system with a very high hydrogen evolution rate up to ca. 1 μmol s−1 under the illumination of a standard Pt-decorated carbon nitride. The system can achieve a remarkable TOF up to 1.8×106 moles of hydrogen per mole of Pt per hour under mild conditions. The total turnover number (TTN) of 470 000 measured over 38 hours is among the highest reported. The system does not lead to any COx emissions, hence it could feed clean hydrogen to fuel cells. In contrast to a slurry system, the proposed multi-layer system avoids particle aggregation and effectively uses light and Pt active sites. The performance is also attributed to the light-triggered reforming of alkaline methanol. This notable performance is a promising step toward practical light-driven hydrogen generation.
5.
S Rieger, T Fürmann, J K Stolarczyk, J Feldmann
Optically Induced Coherent Phonons in Bismuth Oxyiodide (BiOI) Nanoplatelets Journal Article
In: Nano Letters, 2021, ISSN: 1530-6984.
@article{,
title = {Optically Induced Coherent Phonons in Bismuth Oxyiodide (BiOI) Nanoplatelets},
author = {S Rieger and T F\"{u}rmann and J K Stolarczyk and J Feldmann},
url = {https://doi.org/10.1021/acs.nanolett.1c00530},
doi = {10.1021/acs.nanolett.1c00530},
issn = {1530-6984},
year = {2021},
date = {2021-06-30},
journal = {Nano Letters},
abstract = {Bismuth oxyiodide (BiOI) is a promising material for photocatalysis combining intriguing optical and structural properties. We show that excitation by a femtosecond laser pulse creates coherent phonons inducing a time-variant oscillating modulation of the optical density. We find that the two underlying frequencies originate from lattice vibrations along the [001] crystallographic axis, the stacking direction of oppositely charged layers in BiOI. This is consistent with a subpicosecond charge separation driven by a built-in dipolar field. This partially screens the field, launching coherent phonons. Further, we determine the two major dephasing mechanisms that lead to the loss of vibronic coherence: (i) the anharmonic decay of an optical phonon into two acoustic phonons and (ii) phonon-carrier scattering. Our results provide a direct demonstration of the presence of an electric field in BiOI along the [001] axis and show its role in efficient charge separation that is crucial for photocatalytic applications of BiOI.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Bismuth oxyiodide (BiOI) is a promising material for photocatalysis combining intriguing optical and structural properties. We show that excitation by a femtosecond laser pulse creates coherent phonons inducing a time-variant oscillating modulation of the optical density. We find that the two underlying frequencies originate from lattice vibrations along the [001] crystallographic axis, the stacking direction of oppositely charged layers in BiOI. This is consistent with a subpicosecond charge separation driven by a built-in dipolar field. This partially screens the field, launching coherent phonons. Further, we determine the two major dephasing mechanisms that lead to the loss of vibronic coherence: (i) the anharmonic decay of an optical phonon into two acoustic phonons and (ii) phonon-carrier scattering. Our results provide a direct demonstration of the presence of an electric field in BiOI along the [001] axis and show its role in efficient charge separation that is crucial for photocatalytic applications of BiOI.
4.
A Dey, J Ye, A De, E Debroye, S K Ha, E Bladt, A S Kshirsagar, Z Wang, J Yin, Y Wang, L N Quan, F Yan, M Gao, X Li, J Shamsi, T Debnath, M Cao, M A Scheel, S Kumar, J A Steele, M Gerhard, L Chouhan, K Xu, X-G Wu, Y Li, Y Zhang, A Dutta, C Han, I Vincon, A L Rogach, A Nag, A Samanta, B A Korgel, C-J Shih, D R Gamelin, D H Son, H Zeng, H Zhong, H Sun, H V Demir, I G Scheblykin, I Mora-Seró, J K Stolarczyk, J Z Zhang, J Feldmann, J Hofkens, J M Luther, J Pérez-Prieto, L Li, L Manna, M I Bodnarchuk, M V Kovalenko, M B J Roeffaers, N Pradhan, O F Mohammed, O M Bakr, P Yang, P Müller-Buschbaum, P V Kamat, Q Bao, Q Zhang, R Krahne, R E Galian, S D Stranks, S Bals, V Biju, W A Tisdale, Y Yan, R L Z Hoye, L Polavarapu
State of the Art and Prospects for Halide Perovskite Nanocrystals Journal Article
In: ACS Nano, 2021, ISSN: 1936-0851.
@article{,
title = {State of the Art and Prospects for Halide Perovskite Nanocrystals},
author = {A Dey and J Ye and A De and E Debroye and S K Ha and E Bladt and A S Kshirsagar and Z Wang and J Yin and Y Wang and L N Quan and F Yan and M Gao and X Li and J Shamsi and T Debnath and M Cao and M A Scheel and S Kumar and J A Steele and M Gerhard and L Chouhan and K Xu and X-G Wu and Y Li and Y Zhang and A Dutta and C Han and I Vincon and A L Rogach and A Nag and A Samanta and B A Korgel and C-J Shih and D R Gamelin and D H Son and H Zeng and H Zhong and H Sun and H V Demir and I G Scheblykin and I Mora-Ser\'{o} and J K Stolarczyk and J Z Zhang and J Feldmann and J Hofkens and J M Luther and J P\'{e}rez-Prieto and L Li and L Manna and M I Bodnarchuk and M V Kovalenko and M B J Roeffaers and N Pradhan and O F Mohammed and O M Bakr and P Yang and P M\"{u}ller-Buschbaum and P V Kamat and Q Bao and Q Zhang and R Krahne and R E Galian and S D Stranks and S Bals and V Biju and W A Tisdale and Y Yan and R L Z Hoye and L Polavarapu},
url = {https://doi.org/10.1021/acsnano.0c08903},
doi = {10.1021/acsnano.0c08903},
issn = {1936-0851},
year = {2021},
date = {2021-06-17},
urldate = {2021-06-17},
journal = {ACS Nano},
abstract = {Metal-halide perovskites have rapidly emerged as one of the most promising materials of the 21st century, with many exciting properties and great potential for a broad range of applications, from photovoltaics to optoelectronics and photocatalysis. The ease with which metal-halide perovskites can be synthesized in the form of brightly luminescent colloidal nanocrystals, as well as their tunable and intriguing optical and electronic properties, has attracted researchers from different disciplines of science and technology. In the last few years, there has been a significant progress in the shape-controlled synthesis of perovskite nanocrystals and understanding of their properties and applications. In this comprehensive review, researchers having expertise in different fields (chemistry, physics, and device engineering) of metal-halide perovskite nanocrystals have joined together to provide a state of the art overview and future prospects of metal-halide perovskite nanocrystal research.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Metal-halide perovskites have rapidly emerged as one of the most promising materials of the 21st century, with many exciting properties and great potential for a broad range of applications, from photovoltaics to optoelectronics and photocatalysis. The ease with which metal-halide perovskites can be synthesized in the form of brightly luminescent colloidal nanocrystals, as well as their tunable and intriguing optical and electronic properties, has attracted researchers from different disciplines of science and technology. In the last few years, there has been a significant progress in the shape-controlled synthesis of perovskite nanocrystals and understanding of their properties and applications. In this comprehensive review, researchers having expertise in different fields (chemistry, physics, and device engineering) of metal-halide perovskite nanocrystals have joined together to provide a state of the art overview and future prospects of metal-halide perovskite nanocrystal research.
3.
J Fang, T Debnath, S Bhattacharyya, M Döblinger, J Feldmann, J K Stolarczyk
Photobase effect for just-in-time delivery in photocatalytic hydrogen generation Journal Article
In: Nature Communications, vol. 11, no. 1, pp. 5179, 2020, ISSN: 2041-1723.
@article{nokey,
title = {Photobase effect for just-in-time delivery in photocatalytic hydrogen generation},
author = {J Fang and T Debnath and S Bhattacharyya and M D\"{o}blinger and J Feldmann and J K Stolarczyk},
url = {https://doi.org/10.1038/s41467-020-18583-6},
doi = {10.1038/s41467-020-18583-6},
issn = {2041-1723},
year = {2020},
date = {2020-10-14},
journal = {Nature Communications},
volume = {11},
number = {1},
pages = {5179},
abstract = {Carbon dots (CDs) are a promising nanomaterial for photocatalytic applications. However, the mechanism of the photocatalytic processes remains the subject of a debate due to the complex internal structure of the CDs, comprising crystalline and molecular units embedded in an amorphous matrix, rendering the analysis of the charge and energy transfer pathways between the constituent parts very challenging. Here we propose that the photobasic effect, that is the abstraction of a proton from water upon excitation by light, facilitates the photoexcited electron transfer to the proton. We show that the controlled inclusion in CDs of a model photobase, acridine, resembling the molecular moieties found in photocatalytically active CDs, strongly increases hydrogen generation. Ultrafast spectroscopy measurements reveal proton transfer within 30 ps of the excitation. This way, we use a model system to show that the photobasic effect may be contributing to the photocatalytic H2 generation of carbon nanomaterials and suggest that it may be tuned to achieve further improvements. The study demonstrates the critical role of the understanding the dynamics of the CDs in the design of next generation photocatalysts.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Carbon dots (CDs) are a promising nanomaterial for photocatalytic applications. However, the mechanism of the photocatalytic processes remains the subject of a debate due to the complex internal structure of the CDs, comprising crystalline and molecular units embedded in an amorphous matrix, rendering the analysis of the charge and energy transfer pathways between the constituent parts very challenging. Here we propose that the photobasic effect, that is the abstraction of a proton from water upon excitation by light, facilitates the photoexcited electron transfer to the proton. We show that the controlled inclusion in CDs of a model photobase, acridine, resembling the molecular moieties found in photocatalytically active CDs, strongly increases hydrogen generation. Ultrafast spectroscopy measurements reveal proton transfer within 30 ps of the excitation. This way, we use a model system to show that the photobasic effect may be contributing to the photocatalytic H2 generation of carbon nanomaterials and suggest that it may be tuned to achieve further improvements. The study demonstrates the critical role of the understanding the dynamics of the CDs in the design of next generation photocatalysts.
2.
S Rieger, B J Bohn, M Doblinger, A F Richter, Y Tong, K Wang, P Muller-Buschbaum, L Polavarapu, L Leppert, J K Stolarczyk, J Feldmann
Excitons and narrow bands determine the optical properties of cesium bismuth halides Journal Article
In: Physical Review B, vol. 100, no. 20, 2019, ISSN: 2469-9950.
@article{,
title = {Excitons and narrow bands determine the optical properties of cesium bismuth halides},
author = {S Rieger and B J Bohn and M Doblinger and A F Richter and Y Tong and K Wang and P Muller-Buschbaum and L Polavarapu and L Leppert and J K Stolarczyk and J Feldmann},
url = {\<Go to ISI\>://WOS:000498055800001},
doi = {10.1103/PhysRevB.100.201404},
issn = {2469-9950},
year = {2019},
date = {2019-11-20},
journal = {Physical Review B},
volume = {100},
number = {20},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
1.
A Mähringer, A C Jakowetz, J M Rotter, B J Bohn, J K Stolarczyk, J Feldmann, T Bein, D D Medina
Oriented Thin Films of Electroactive Triphenylene Catecholate-Based Two-Dimensional Metal–Organic Frameworks Journal Article
In: ACS Nano, vol. 13, no. 6, pp. 6711-6719, 2019, ISSN: 1936-0851.
@article{nokey,
title = {Oriented Thin Films of Electroactive Triphenylene Catecholate-Based Two-Dimensional Metal\textendashOrganic Frameworks},
author = {A M\"{a}hringer and A C Jakowetz and J M Rotter and B J Bohn and J K Stolarczyk and J Feldmann and T Bein and D D Medina},
url = {https://doi.org/10.1021/acsnano.9b01137},
doi = {10.1021/acsnano.9b01137},
issn = {1936-0851},
year = {2019},
date = {2019-05-02},
journal = {ACS Nano},
volume = {13},
number = {6},
pages = {6711-6719},
abstract = {Two-dimensional triphenylene-based metal\textendashorganic frameworks (TP-MOFs) attract significant scientific interest due to their long-range order combined with significant electrical conductivity. The deposition of these structures as oriented films is expected to promote their incorporation into diverse optoelectronic devices. However, to date, a controlled deposition strategy applicable for the different members of this MOF family has not been reported yet. Herein, we present the synthesis of highly oriented thin films of TP-MOFs by vapor-assisted conversion (VAC). We targeted the M-CAT-1 series comprising hexahydroxytriphenylene organic ligands and metal-ions such as Ni2+, Co2+, and Cu2+. These planar organic building blocks are connected in-plane to the metal-ions through a square planar node forming extended sheets which undergo self-organization into defined stacks. Highly oriented thin Ni- and Co-CAT-1 films grown on gold substrates feature a high surface coverage with a uniform film topography and thickness ranging from 180 to 200 nm. The inclusion of acid modulators in the synthesis enabled the growth of films with a preferred orientation on quartz and on conductive substrates such as indium-doped tin oxide (ITO). The van der Pauw measurements performed across the M-CAT-1 films revealed high electrical conductivity values of up to 10\textendash3 S cm\textendash1 for both the Ni- and Co-CAT-1 films. Films grown on quartz allowed for a detailed photophysical characterization by means of UV\textendashvis, photoluminescence, and transient absorption spectroscopy. The latter revealed the existence of excited states on a nanosecond time scale, sufficiently long to demonstrate a photoinduced charge generation and extraction in Ni-CAT-1 films. This was achieved by fabricating a basic photovoltaic device with an ITO/Ni-CAT-1/Al architecture, thus establishing this MOF as a photoactive material. Our results point to the intriguing capabilities of these conductive M-CAT-1 materials and an additional scope of applications as photoabsorbers enabled through VAC thin-film synthesis.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Two-dimensional triphenylene-based metal–organic frameworks (TP-MOFs) attract significant scientific interest due to their long-range order combined with significant electrical conductivity. The deposition of these structures as oriented films is expected to promote their incorporation into diverse optoelectronic devices. However, to date, a controlled deposition strategy applicable for the different members of this MOF family has not been reported yet. Herein, we present the synthesis of highly oriented thin films of TP-MOFs by vapor-assisted conversion (VAC). We targeted the M-CAT-1 series comprising hexahydroxytriphenylene organic ligands and metal-ions such as Ni2+, Co2+, and Cu2+. These planar organic building blocks are connected in-plane to the metal-ions through a square planar node forming extended sheets which undergo self-organization into defined stacks. Highly oriented thin Ni- and Co-CAT-1 films grown on gold substrates feature a high surface coverage with a uniform film topography and thickness ranging from 180 to 200 nm. The inclusion of acid modulators in the synthesis enabled the growth of films with a preferred orientation on quartz and on conductive substrates such as indium-doped tin oxide (ITO). The van der Pauw measurements performed across the M-CAT-1 films revealed high electrical conductivity values of up to 10–3 S cm–1 for both the Ni- and Co-CAT-1 films. Films grown on quartz allowed for a detailed photophysical characterization by means of UV–vis, photoluminescence, and transient absorption spectroscopy. The latter revealed the existence of excited states on a nanosecond time scale, sufficiently long to demonstrate a photoinduced charge generation and extraction in Ni-CAT-1 films. This was achieved by fabricating a basic photovoltaic device with an ITO/Ni-CAT-1/Al architecture, thus establishing this MOF as a photoactive material. Our results point to the intriguing capabilities of these conductive M-CAT-1 materials and an additional scope of applications as photoabsorbers enabled through VAC thin-film synthesis.