Modulating charge separation and transfer for high-performance photoelectrodes via built-in electric field

Abstract

Constructing a built-in electric field has emerged as a key strategy for enhancing charge separation and transfer, thereby improving photoelectrochemical performance. Recently, considerable efforts have been devoted to this endeavor. This review systematically summarizes the impact of built-in electric fields on enhancing charge separation and transfer mechanisms, focusing on the modulation of built-in electric fields in terms of depth and orderliness. First, mechanisms and tuning strategies for built-in electric fields are explored. Then, the state-of-the-art works regarding built-in electric fields for modulating charge separation and transfer are summarized and categorized according to surface and interface depth. Finally, current strategies for constructing bulk built-in electric fields in photoelectrodes are explored, and insights into future developments for enhancing charge separation and transfer in high-performance photoelectrochemical applications are provided.

Keywords

photoelectrochemical water splitting / bulk built-in electric field / cation intercalation / charge separation and transfer

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