Dual rare earth atomic sites with a conjugated electronic structure for efficient photocatalytic water splitting

Abstract

The surface active sites of semiconductor materials are crucial for achieving excellent photocatalytic performance. Herein, Eu and Ce dual rare-earth metal atomic active sites with a conjugated electronic structure were constructed on the surface of B-doped TiO₂ through an atomic confinement strategy. Under the optimized conditions, the as-prepared photocatalyst (CeEu–BTO) achieved hydrogen evolution rates of 558.6 μmol g⁻¹ h⁻¹ (freshwater) and 232.7 μmol g⁻¹ h⁻¹ (seawater) with apparent quantum yields (AQYs) of 22.17% and 5.07%, respectively. The experimental and density functional theoretical calculation results suggested that the excellent photocatalytic activity of CeEu–BTO primarily stemmed from the boron-bridged Ce and Eu atomic active sites (Ce–B–Eu) that have strong electronic interactions with TiO₂. The formed Ce–B–Eu active sites can broaden light absorption, improve the separation efficiency of photogenerated carriers, and reduce the activation barriers for H⁺ reduction. This work provides a new strategy for the design of efficient rare earth metal-coupled semiconductor photocatalysts.