Synergistic water oxidation and reduction over ruthenium phosphide catalytic sites towards photocatalytic degradation of emerging contaminants coupled with hydrogen production

•Bifunctional cocatalysts of RuP was developed for efficient photocatalytic removal of pollutants and hydrogen production.•Hydrogen evolution rate and degradation efficiency of RuP were 6.7 and 1.4 times than Ru-CNS.•RuP promoted the adsorption and reduced the activation energy barriers of water molecules.•RuP enhanced the separation and migration of photogenerated carriers. As an advanced redox process for sustainable water treatment, photocatalytic oxidation of organic pollutants coupled with water reduction for hydrogen production remains thermodynamically challenging. In this work, we constructed carbon nitride microspheres loaded with ruthenium phosphide cocatalysts (RuP-CNS), which can be utilized to the system for efficient photocatalytic removal of the pharmaceuticals and personal care products as well as the conversion of wastewater to hydrogen. RuP-CNS exhibits superior photocatalytic activity with a degradation efficiency of 94.17 % and a hydrogen evolution rate of 1917.26 μmol·g−1 within two hours in treating the simulated wastewater containing naproxen (NPX). Experimental and theoretical calculation results disclose that the introduction of the RuP cocatalyst not only promotes the adsorption of water molecules and reduces the activation energy barriers of water oxidation reaction, thus accelerating the generation of ·OH radicals, which contributed to the improvement of the activity of photocatalytic oxidative degradation of emerging contaminants. It also reduces the overpotential of hydrogen precipitation, coordinates the oxidation reaction rate, and inhibits the recombination of photogenerated carriers, thereby accelerating hydrogen generation. This work underscores the importance of bifunctional cocatalysts to realize photocatalytic removal of organic pollutants and efficient conversion of wastewater to H2.