Activating 2D MoS2 by loading 2D Cu–S nanoplatelets for improved visible light photocatalytic hydrogen evolution, drug degradation, and CO2 reduction

Abstract

Finding reliable photocatalysts capable of driving reactions using only sunlight is more needed than ever. A variety of strategies to harvest sunlight and convert it into chemical energy have been successfully utilized such as synthesizing nanostructures, using metal nanoparticles, doping, and others. In this work, we discover a facile way to anchor CuS nanoplatelets on 2D MoS₂ by the solvothermal method using ethylene glycol (EG) as both a reduction agent and an exfoliating agent of bulk MoS₂. Using CuS as a co-catalysis on MoS₂ with their huge surface areas, led to improved photocatalytic activity for three different applications including H₂ evolution, CO₂ reduction, and endosulfan degradation. Specifically, Cu–S@MoS₂ 3% nanocomposite produced 9.86 μmol g⁻¹ h⁻¹ of H₂, 0.48 μmol g⁻¹ h⁻¹ of CO and full decomposition of endosulfan within 6 h. The Cu-loaded MoS₂ nanocomposites were thoroughly characterized by spectroscopic (including synchrotron-based spectroscopy) and microscopic methods to understand the formation of Cu–S during the solvothermal process. Moreover, the role of the EG during the synthetic procedure was revealed experimentally and studied theoretically via DFT simulations.