Highly efficient reduction of 4-nitrophenol by the Au/MoS2 catalyst with the promotion of cobalt introduction

Abstract

The serious problems caused by water contamination call for efficient treatment. The catalytic reduction of 4-nitrophenol (4-NP) by NaBH₄ in solution is a convenient way to convert 4-NP to 4-aminophenol (4-AP), which is a precious intermediate for manufacturing of important materials such as pharmaceuticals. In the present study, the Co modified MoS₂ supported Au nanoparticles (Au/Co-MoS₂) is proved to be an efficient catalyst for the reduction of 4-NP. With the introduction of cobalt, the catalytic activity is improved obviously compared to Au/MoS₂. When Co:Mo is 2:8 (mol), the Au/CoMoS₂(2/8) catalyst exhibits the highest activity. The kinetics of the catalytic reactions were studied by the plot of ln(C_t/C₀) against reaction time and the k_app for Au/CoMoS₂(2/8) is 1.063 min⁻¹. The characterization of the catalysts shows that the addition of cobalt can create more crystal defects, promote the exposure of active edge sites, facilitate the surface of catalysts to be more reactive.