Photocatalytic hydrazine-assisted reduction of nitroarenes promoted by Cu dopant modulated In 2 S 3 at ambient condition

Abstract

The efficient reduction of nitroarenes to the corresponding amines is of great significance in the chemical industry. However, the conventional thermocatalysis route usually involves harsh reaction conditions (e.g., high temperature, pressurized hydrogen, and anaerobic atmospheres) and relies on precious metals or long reaction time. Herein, we cast an alternative protocol with Cu-doped In2S3 (Cu/In2S3 ) semiconductor for photocatalytic CO2 emission-free hydrogenation of nitroarenes.Density functional theory (DFT) simulations and in situ characterization results demonstrate that Cu doping in In2S3 introduces intermediate energy levels, and the doped Cu site serves as a trapping site for photogenerated holes, prolonging the lifetime of charge carriers, and optimizing the adsorption capacity of reactants. The above features, combined with strong energy band coupling between photoactive Cu/In2S3 and carbon-free hydrazine as hole scavenger, enable an efficient and environmentally friendly (without carbon emission) photocatalytic hydrogenation of nitroarenes at ambient condition (without inert gas protection) and visible light irradiation. In addition, the current hydrogenation system shows broad reaction scope, good stability, easily recyclable and scalable traits, demonstrating great practical potential.