@article{,
title = {Self-activation of copper electrodes during CO electro-oxidation in alkaline electrolyte},
author = {A Auer and M Andersen and E-M Wernig and N G H\"{o}rmann and N Buller and K Reuter and J Kunze-Liebh\"{a}user},
url = {https://doi.org/10.1038/s41929-020-00505-w},
doi = {10.1038/s41929-020-00505-w},
issn = {2520-1158},
year = {2020},
date = {2020-09-07},
journal = {Nature Catalysis},
abstract = {The development of low-temperature fuel cells for clean energy production is an appealing alternative to fossil-fuel technologies. CO is a key intermediate in the electro-oxidation of energy carrying fuels and, due to its strong interaction with state-of-the-art Pt electrodes, it is known to act as a poison. Here we demonstrate the ability of Earth-abundant Cu to electro-oxidize CO efficiently in alkaline media, reaching high current densities of ≥0.35 mA cm−2 on single-crystal Cu(111) model catalysts. Strong and continuous surface structural changes are observed under reaction conditions. Supported by first-principles microkinetic modelling, we show that the concomitant presence of high-energy undercoordinated Cu structures at the surface is a prerequisite for the high activity. Similar CO-induced self-activation has been reported for gas\textendashsurface reactions at coinage metals, demonstrating the strong parallels between heterogeneous thermal catalysis and heterogeneous electrocatalysis.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{,
title = {Near-atomic-scale observation of grain boundaries in a layer-stacked two-dimensional polymer},
author = {H Y Qi and H Sahabudeen and B K Liang and M Polozij and M A Addicoat and T E Gorelik and M Hambsch and M Mundszinger and S Park and B V Lotsch and S C B Mannsfeld and Z K Zheng and R H Dong and T Heine and X L Feng and U Kaiser},
url = {<Go to ISI>://WOS:000560465800030},
doi = {10.1126/sciadv.abb5976},
issn = {2375-2548},
year = {2020},
date = {2020-08-14},
journal = {Science Advances},
volume = {6},
number = {33},
abstract = {Two-dimensional (2D) polymers, hold great promise in the rational materials design tailored for next-generation applications. However, little is known about the grain boundaries in 2D polymers, not to mention their formation mechanisms and potential influences on the material's functionalities. Using aberration-corrected high-resolution transmission electron microscopy, we present a direct observation of the grain boundaries in a layer-stacked 2D polyimine with a resolution of 2.3 angstrom, shedding light on their formation mechanisms. We found that the polyimine growth followed a "birth-and-spread" mechanism. Antiphase boundaries implemented a self-correction to the missing-linker and missing-node defects, and tilt boundaries were formed via grain coalescence. Notably, we identified grain boundary reconstructions featuring closed rings at tilt boundaries. Quantum mechanical calculations revealed that boundary reconstruction is energetically allowed and can be generalized into different 2D polymer systems. We envisage that these results may open up the opportunity for future investigations on defect-property correlations in 2D polymers.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{,
title = {Revealing Nanoscale Chemical Heterogeneities in Polycrystalline Mo-BiVO(4)Thin Films},
author = {J Eichhorn and S E Reyes-Lillo and S Roychoudhury and S Sallis and J Weis and D M Larson and J K Cooper and I D Sharp and D Prendergast and F M Toma},
url = {<Go to ISI>://WOS:000555446200001},
doi = {10.1002/smll.202001600},
issn = {1613-6810},
year = {2020},
date = {2020-08-01},
journal = {Small},
abstract = {The activity of polycrystalline thin film photoelectrodes is impacted by local variations of the material properties due to the exposure of different crystal facets and the presence of grain/domain boundaries. Here a multi-modal approach is applied to correlate nanoscale heterogeneities in chemical composition and electronic structure with nanoscale morphology in polycrystalline Mo-BiVO4. By using scanning transmission X-ray microscopy, the characteristic structure of polycrystalline film is used to disentangle the different X-ray absorption spectra corresponding to grain centers and grain boundaries. Comparing both spectra reveals phase segregation of V(2)O(5)at grain boundaries of Mo-BiVO(4)thin films, which is further supported by X-ray photoelectron spectroscopy and many-body density functional theory calculations. Theoretical calculations also enable to predict the X-ray absorption spectral fingerprint of polarons in Mo-BiVO4. After photo-electrochemical operation, the degraded Mo-BiVO(4)films show similar grain center and grain boundary spectra indicating V(2)O(5)dissolution in the course of the reaction. Overall, these findings provide valuable insights into the degradation mechanism and the impact of material heterogeneities on the material performance and stability of polycrystalline photoelectrodes.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}