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arXiv · 2112.05959

Developing Dipole-scheme Heterojunction Photocatalysts

Xu Gao·Yanqing Shen·Jiajia Liu·Lingling Lv·Min Zhou·Zhongxiang Zhou·Yuan Ping Feng·Lei Shen
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Abstract

The high recombination rate of photogenerated carriers is the bottleneck of photocatalysis, severely limiting the photocatalytic efficiency. Here, we develop a dipole-scheme (D-scheme for short) photocatalytic model and materials realization. The D-scheme heterojunction not only can effectively separate electrons and holes by a large polarization field, but also boosts photocatalytic redox reactions with large driving photovoltages and without any carrier loss. By means of first-principles and GW calculations, we propose a D-scheme heterojunction prototype with two real polar materials, PtSeTe/LiGaS2. This D-scheme photocatalyst exhibits a high capability of the photogenerated carrier separation and near-infrared light absorption. Moreover, our calculations of the Gibbs free energy imply a high ability of the hydrogen and oxygen evolution reaction by a large driving force. The proposed D-scheme photocatalytic model is generalized and paves a valuable route of significantly improving the photocatalytic efficiency.

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Xu Gao, Yanqing Shen, Jiajia Liu, Lingling Lv, Min Zhou, Zhongxiang Zhou, Yuan Ping Feng, Lei Shen. 2021-12-11. Developing Dipole-scheme Heterojunction Photocatalysts. https://doi.org/10.1016/j.apsusc.2022.153942

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