MoS2-wrapped Mn0.2Cd0.8S nanospheres towards efficient photocatalytic H2 generation and CO2 reduction

Abstract

Herein, a series of MoS₂-wrapped Mn_0.2Cd_0.8S nanospheres with different MoS₂ content were fabricated via a two-step hydrothermal route. The photocatalytic activity of the as-prepared MoS₂/Mn_0.2Cd_0.8S composites for H₂ production and reduction of CO₂ under visible light irradiation was investigated. The results demonstrated that the ultra-thin MoS₂ nanosheets were uniformly wrapped on the surface of cauliflower-like Mn_0.2Cd_0.8S nanospheres, and an intimate interfacial contact was formed between MoS₂ and Mn_0.2Cd_0.8S. The MoS₂/Mn_0.2Cd_0.8S hybrids exhibited significantly enhanced photocatalytic activity compared with the pristine Mn_0.2Cd_0.8S. The optimal MoS₂ loading content was determined to be 3.0 wt%, giving a H₂ production rate of 335.02 μmol h⁻¹ and a CH₃OH production rate of 2.13 μmol h⁻¹, which were around 5.1 and 5.4 times that of bare Mn_0.2Cd_0.8S, respectively. The superior photocatalytic activity was predominantly attributed to the intimate contacts between Mn_0.2Cd_0.8S and MoS₂, which facilitated the transfer and separation of the photoexcited charge carriers. Moreover, the as-synthesized MoS₂/Mn_0.2Cd_0.8S composites also showed excellent stability. This study demonstrates the great potential of MoS₂-wrapped Mn_0.2Cd_0.8S as a noble-metal-free catalyst for photocatalytic energy conversion.