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arXiv · 1809.09712

Voltage-dependent reconstruction of layered Bi$_2$WO$_6$ and Bi$_2$MoO$_6$ photocatalysts and its influence on charge separation for water splitting

Quinn Campbell·Daniel Fisher·Ismaila Dabo
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Abstract

We study the surface stability of the layered bismuth-oxide Bi$_2$WO$_6$ and Bi$_2$MoO$_6$ photocatalysts, which belong to the series of Aurivillius (Bi$_2$A$_{n-1}$B$_{n}$O$_{3n+3}$) perovskites and have been proposed as efficient visible-light absorbers, due to favorable electronic hybridization induced by the Bi 6s and 6p orbitals. We present a Newton--Raphson optimization of the charge distribution at the semiconductor--solution interface using the self-consistent continuum solvation (SCCS) model to describe the influence of the aqueous environment. Our analysis provides a description of the charged interface under controlled pH and applied voltage, and offers a molecular interpretation of the competing structural and electrical factors that underlie the facet-dependent photocatalytic activity of layered Bi$_2$A$_{n-1}$B$_{n}$O$_{3n+3}$ compounds.

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Quinn Campbell, Daniel Fisher, Ismaila Dabo. 2018-09-25. Voltage-dependent reconstruction of layered Bi$_2$WO$_6$ and Bi$_2$MoO$_6$ photocatalysts and its influence on charge separation for water splitting. https://doi.org/10.1103/physrevmaterials.3.015404

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