Electrochemical stability and light-harvesting ability of silicon photoelectrodes in aqueous environments

Quinn Campbell; Ismaila Dabo

doi:10.1063/1.5093810

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arXiv · 1808.00392

Electrochemical stability and light-harvesting ability of silicon photoelectrodes in aqueous environments

Quinn Campbell·Ismaila Dabo

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Abstract

We consider the factors that affect the photoactivity of silicon electrodes for the water-splitting reaction using a self-consistent continuum solvation (SCCS) model of the solid-liquid interface. This model allows us to calculate the charge-voltage response, Schottky barriers, and surface stability of different terminations while accounting for the interactions between the charge-pinning centers at the surface and the depletion region of the semiconductor. We predict that the most stable oxidized surface does not have a favorable Schottky barrier, which further explains the low solar-to-hydrogen performance of passivated silicon electrodes.

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Quinn Campbell, Ismaila Dabo. 2018-08-01. Electrochemical stability and light-harvesting ability of silicon photoelectrodes in aqueous environments. https://doi.org/10.1063/1.5093810

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