Bimetallic CoNi-metal–organic framework@molybdenum disulfide core–shell Z-scheme heterojunctions with broad-spectrum response toward optimized photocatalytic performance

Abstract

This work reports the effective preparation of a bimetallic metal–organic framework CoNi-MOF@MoS₂ core–shell Z-scheme heterojunction photocatalyst via a two-step hydrothermal method. MoS₂ nanoflowers uniformly grow on the multilayer CoNi-MOF exterior. MoS₂ can be added to the system to improve its specific surface area and provide enough surface active sites for photocatalysis. The resultant CoNi-MOF@MoS₂ has a broad-spectrum response, which is favorable for promoting the photocatalytic process. Under visible light irradiation, CoNi-MOF@MoS₂ has a high hydrogen evolution efficiency of 478.6 μmol h⁻¹ g⁻¹. It also activates peroxymonosulfate, and the photocatalytic degradation rate of RhB pollutants in water can be up to 99.3% within 40 min, which is several times higher than that of the CoNi-MOF. The presence of the distinctive core–shell Z-scheme heterojunction structure is responsible for efficient charge separation and the enhanced photocatalytic performance. The high stability of CoNi-MOF@MoS₂ also implies its potential applications in fields of environment and energy in future.