Metal-free plasmonic boron phosphide/graphitic carbon nitride with core-shell structure photocatalysts for overall water splitting

Abstract

In this work, we report a novel metal-free plasmonic boron phosphide/graphitic carbon nitride (BP@g-C3N4) catalyst for photocatalytic overall water splitting. The BP@C3N4 catalyst exhibits broadened spectral adsorption in UV–vis to NIR region and shows the activity for hydrogen evolution even under 730 nm illumination, which is close to NIR region of solar irradiation. The highest H2 production rate reaches 31.5 μmol g−1 h−1 under visible light irradiation, which is 34.3 and 112.6 times higher than corresponding data of Pt/g-C3N4 and g-C3N4 catalysts respectively without noble metal loading. The finite element frequency-domain simulations indicate that the significantly improved photocatalytic water splitting performance is due to the BP plasmon resonance leading to effectively photo-induced carrier separation and transfer, which is crucially for solar energy harvesting and utilization. The metal-free earth-abundant plasmonic BP@g-C3N4 can catalyze photocatalytic overall water splitting by the plasmonic effect under visible light and near infrared irradiation efficiently.