Progress on Si-based photoelectrodes for industrial production of green hydrogen by solar-driven water splitting

Abstract

Solar power has been regarded as the ultimate green-energy source because of its inexhaustibility and eco-friendliness. The solar-driven water-splitting technology for green hydrogen production is considered to be one of effective ways for solar energy harvesting and storage, which may provide solutions for the energy crisis and environmental issues. In the past decades, great progress has been achieved in this area. Photoelectrochemical (PEC) water splitting is especially promising for the production of solar fuels because of expected large-scale industrial application. Silicon (Si), as an ideal candidate for the photoelectrode, is the most suitable material for the PEC device in industrial photocatalytic water splitting because of its abundance, mature fabrication technology, and suitable band gap. Here, we give a systematic review on the recent progress for Si-based photoelectrodes for water splitting with a focus on the industrial application. Particularly, the strategies, such as band-alignment control, morphology design, and surface engineering, are summarized to enhance the PEC performance and durability for practical application. Furthermore, the perspective for the design of commercial Si-based PEC devices with high PEC performance, long-term stability, large-size, and low cost are given at the end, which shall guide the development of PEC water splitting for industrial application.