Photocatalytic Hydrogen Production from Pure Water Using a IEF-11/g-C3N4 S-Scheme Heterojunction.

Abstract

Construction of S-scheme heterojunction offers a promising way to enhance the photocatalytic performance of photocatalysts for converting solar energy into chemical energy. However, the photocatalytic H2 production in pure water without sacrificial agents is still a challenge. Herein, the IEF-11 with the best photocatalytic H2 production performance in MOFs and suitable band structure was selected and firstly constructed with g-C3N4 to obtain a S-scheme heterojunction for photocatalytic H2 production from pure water. As a result, the novel IEF-11/g-C3N4 heterojunction photocatalysts exhibited significantly improved photocatalytic H2 production performance in pure water without any sacrificial agent, with a rate of 576 μmol/g/h, which is about 8 times than that of g-C3N4 and 23 times of IEF-11. The novel IEF-11/g-C3N4 photocatalysts also had a photocatalytic H2 production rate of up to 92 μmol/g/h under visible light and a good photocatalytic stability. The improved performance can be attributed to the efficient separation of photogenerated charge carriers, faster charge transfer efficiency and longer photogenerated carrier lifetimes, which comes from the forming of S-scheme heterojunction in the IEF-11/g-C3N4 photocatalyst. This work is a promising guideline for obtaining MOF-based or g-C3N4-based photocatalysts with great photocatalytic water splitting performance.