Modifying photocatalysts for solar hydrogen evolution based on the electron behavior

Abstract

Converting abundant solar energy into precious and clean hydrogen energy through photocatalytic water splitting is a highly promising way to address energy shortages. Solar H₂ evolution is a practical technology in the environmental and energy fields. The electron is the protagonist in solar H₂ evolution and the electron behavior determines performance. Three pivotal steps, electron generation, electron survival and electron utilization, are involved in this photocatalytic process. This review discusses some typical cases from the last two years of improving the performance of solar H₂ evolution through elaborately manipulating the electron behavior. The manipulation can be accomplished by modifying the photocatalyst itself (self-modification) and with the assistance of foreign materials (extra-modification). It is expected that the main ideas behind these strategies can be extracted and used when designing efficient and robust photocatalytic systems in the future.