Excellent photoelectrochemical hydrogen evolution performance of FeSe2 nanorod/ZnSe 0D/1D heterostructure as efficiency carriers migrate channel

Abstract In the photoelectrochemistry reaction, the electrode is most important. As a common electrode material, the metal oxide has a large band gap and high internal resistance, which is disadvantageous for photocatalytic hydrogen production. Metal selenide generally has a narrow band gap and low internal resistance, which is a promising new type of photocatalyst. A FeSe2/ZnSe heterojunction photocatalyst is constructed by loading ZnSe nanoparticles on FeSe2 nanorods. In this heterostructure, ZnSe is uniformly supported on the surface of FeSe2 to form a 0D/1D structure. Experiments have confirmed that the photoelectrochemical activity and photocatalytic H2 production rate of this heterojunction photocatalyst is greatly improved, and its optimum performance is three times of ZnSe in photoelectrochemical activity and 2.3 times in photocatalytic H2 production rate. Further analysis reveals that the internal resistance of the composite photocatalyst is greatly reduced due to the compositing of FeSe2, and the carrier separation efficiency is also improved. In this FeSe2/ZnSe heterojunction, the conduction band of ZnSe is more negative than that of FeSe2, and the photogenerated electrons generated on the conduction band of ZnSe can be transferred to that of FeSe2, thereby prolonging the carrier lifetime and improving photoelectrochemical activity. This work confirms that FeSe2/ZnSe is a very effective heterostructure, which avoids the addition of precious metals and rare earth metals and shows great application prospects.