@article {1082, title = {Catalysts in electro-, photo- and photoelectrocatalytic CO2 reduction reactions}, journal = {Journal of Photochemistry and Photobiology C: Photochemistry Reviews}, year = {2019}, abstract = {

Published on March 2nd, 2019. Carbon dioxide (CO2) is regarded as a main contributor to the greenhouse effect. As a potential strategy to mitigate its negative impacts, the reduction of CO2 is environmentally critical, economically meaningful and scientifically challenging. Being both thermodynamically and kinetically unfavored, CO2 reduction requires catalysts as a crucial component irrespective of the reaction modes, be it electrocatalytic, photoelectrocatalytic or photocatalytic. In an effort to systematically review the types of catalysts that have been studied for CO2 reduction, we categorize them into two major groups: those being activated by external sources and those being photoexcited and activated themselves. Attention is focused on the detailed mechanisms for each group by which the reduction of CO2 proceeds, yielding a summary of the guiding principles for catalyst designs. This review highlights the importance of mechanistic studies, which permits us to discuss our perspectives on potential directions of catalyst investigation for future catalytic CO2 reduction research.

}, issn = {1389-5567}, doi = {10.1016/j.jphotochemrev.2019.02.002}, url = {http://www.sciencedirect.com/science/article/pii/S1389556718300674}, author = {Yawen Wang and Da He and Hongyu Chen and Dunwei Wang} } @article {1084, title = {Dependence of interface energetics and kinetics on catalyst loading in a photoelectrochemical system}, journal = {Nano Research}, year = {2019}, abstract = {

Published on March 11th, 2019. Solar hydrogen production by the photoelectrochemical method promises a means to store solar energy. While it is generally understood that the process is highly sensitive to the nature of the interface between the semiconductor and the electrolyte, a detailed understanding of this interface is still missing. For instance, few prior studies have established a clear relationship between the interface energetics and the catalyst loading amount. Here we aim to study this relationship on a prototypical Si-based photoelectrochemical system. Two types of interfaces were examined, one with GaN nanowires as a protection layer and one without. It was found that when GaN was present, higher Pt loading (\> 0.1 μg/cm2) led to not only better water reduction (and, hence, hydrogen evolution) kinetics but also more favorable interface energetics for greater photovoltages. In the absence of the protection layer, by stark contrast, increased Pt loading exhibited no measurable influence on the interface energetics, and the main difference was observed only in the hydrogen evolution kinetics. The study sheds new light on the importance of interface engineering for further improvement of photoelectrochemical systems, especially concerning the role of catalysts and protection layers.

}, issn = {1998-0000}, doi = {10.1007/s12274-019-2346-3}, url = {https://doi.org/10.1007/s12274-019-2346-3}, author = {Yumin He and Srinivas Vanka and Tianyue Gao and Da He and Jeremy Espano and Yanyan Zhao and Qi Dong and Chaochao Lang and Yongjie Wang and Thomas W. Hamann and Zetian Mi and Dunwei Wang} }