As an ultimate clean energy, hydrogen production via photocatalytic water splitting under visible-light radiation offers a viable strategy for solving energy and environmental problems simultaneously. The key issue of hydrogen production is to develop active photocatalysts under visible light. Up to now, most photocatalytic water splitting materials are based on transition metal oxides, nitrides and carbides with d0 or d10 configurations. High cost and dissolved metal ions of the photocatalyst materials hinder the wide applications of photocatalysis. As fascinating alternatives to toxic or precious metals and their compounds, 2D metal-free materials are gradually becoming a very important catalyst nowadays.

This chapter summarizes the recent progress on the design and fabrication of 2D metal-free photocatalyst for hydrogen production from water splitting under visible light. A number of metal-free photocatalytic materials will be addressed, including elemental semiconductors, g-C3N4, graphene oxide, B-C-N hybrid sheets, heterojunction photocatalysts, and so on. On the other hand, the universal origin of photocatalytic mechanism and the modification of existing 2D metal-free photocatalysts to improve their photocatalytic activity by various strategies will be also discussed. We aim to giving a comprehensive reference for the scientists in the related fields or the graduate students who want to get known of photocatalyst for hydrogen generation.