Study on the performance and mechanism of photocatalytic hydrogen production by NiO/ZnO-graphene composite materials under low irradiation conditions

Abstract

Using different mass ratios of NiO, ZnO, and corn stover-based graphene (GR), NiO/ZnO-graphene (NZGR) composite photocatalytic materials, which demonstrated photocatalytic water splitting for hydrogen production under low irradiation, were prepared by an in-situ deposition method. The microstructure and optoelectronic properties of the NZGR materials were characterized. The heterostructure formed by NiO and ZnO in the photocatalytic NZGR material was coupled with the graphene-like structure of GR, resulting in the rapid transfer of electrons to the graphene surface, causing electron accumulation and ensuring the ability of the material to produce hydrogen by the photocatalytic decomposition of water under low irradiation. Under the optimal mixing ratio of the components of the NZGR photocatalyst with a graphene mass fraction of 30 %, hydrogen production exhibited the highest rate and was 350 times faster than the photocatalytic hydrogen production of NiO/ZnO under the same conditions. This study provides a new approach to producing hydrogen by the photocatalytic decomposition of water under low irradiation conditions.