Electronic structure methods for simulating the applied potential in semiconductor electrochemistry

Abstract

Semiconductor electrodes (SCEs) play a decisive role in e.g. clean energy conversion technologies but understanding their complex electrochemistry remains an outstanding challenge. Herein, we review electronic structure methods for describing the applied electrode potential in simulations of semiconductor-electrolyte interfaces. We emphasize that inclusion of the electrode potential is significantly more challenging for SCEs than for metallic electrodes because SCEs require accurate models of semiconductor capacitance, including the space-charge region and surface effects, as well as the electrolyte double-layer capacitance. We discuss how these physicochemical complications challenge the development of atomistic models of SCE and how they impact the applicability of the computational hydrogen electrode, capacitance correction, grand canonical DFT, and Green function methods to model SCEs. We highlight the need for continued methodological development and conclude that integrating advanced atomistic models of SCEs with grand canonical, constant inner potential DFT or Green function methods holds promise for accurate SCE simulations.