Au Nanoparticles Embedded in Carbon Self-Doping g-C₃N₄: Facile Photodeposition Method for Superior Photocatalytic H₂ Evolution

Abstract

Developing an efficient and stable photocatalyst for photocatalytic H2 production is of great significance for solving the existing energy and environmental crisis today. Herein, a superior photocatalyst, the uniformly dispersed ultrasmall Au nanoparticle (Au NP) decorated carbon self-doping g-C3N4 nanosheet (PDAu/CCNS), was successfully prepared via a simple photodeposition route. The as-prepared PDAu/CCNS displays a robust photocatalytic hydrogen (H2) production activity (∼15181 μmol h–1 g–1) under visible-light irradiation. The above value is ∼3 times higher than that of the neat carbon self-doping g-C3N4 (CCNS) (5330 μmol h–1 g–1), ∼2 times that of the impregnation Au NP decorated carbon self-doping g-C3N4 (IM-Au/CCNS) (9030 μmol h–1 g–1), and ∼50 times that of the bulk g-C3N4 (BCN) (300 μmol h–1 g–1). The superior photocatalytic performance of the as-prepared PDAu/CCNS results from the evenly distributed ultrasmall Au NPs on CCNS, leading to a strong localized surface plasmon resonance (SPR) effect and an intimate contact between Au NPs and CCNS; thus, the as-prepared PDAu/CCNS exhibits a strong visible-light absorption and a high charge carrier separation and transfer rate, both of which synergistically promote the photocatalytic H2 evolution process.