Abstract:
The photocatalytic production of hydrogen peroxide (H2O2) from water is a promising approach for achieving solar-to-chemical energy conversion as a suitable alternative to obtain hydrogen fuel. Herein, we investigate the effect of heteroatom doping (B, O, P, and S) on the structural, electronic, and photocatalytic properties of graphitic carbon nitride (C3N4) for H2O2 production. A few-layered structure composed of stacked nanosheets was observed for pristine C3N4, while doping induced morphological and structural modifications, including increased disorder, exfoliation, and variations in interlayer spacing, indicating a successful heteroatom incorporation and perturbation of the electronic and optical properties. Photocatalytic tests under simulated sunlight demonstrate the influence of sacrificial agent, pH of the media, and the presence of scavengers on the H2O2 yield. A significant enhancement in H2O2 yield was achieved for all doped-catalysts, with 9.6, 14.8, 11.0, and 16.4-fold enhancement for B-, P-, O-, and S-doped C3N4, respectively, compared to the pristine catalyst. S-doped C3N4 catalyst achieved the highest yield of 3022.1 µmol h−1 g−1 and an apparent quantum yield (AQY) of 8.1 %, due to improved charge separation and optimized selectivity. Mechanistic studies reveal that oxygen activation follows a 2e– pathway, promoted by charge carrier modulation and reactive oxygen species (ROS) dynamics, with singlet oxygen and holes playing a dominant role. The stability of the catalysts is also demonstrated, with S-doped C3N4 maintaining over 95 % efficiency after five cycles. These findings provide new insights into defect engineering for metal-free doping, offering a promising approach for photocatalytic, sustainable H2O2 generation.
Title: Metal-free heteroatom doping of carbon nitride for enhanced photocatalytic hydrogen peroxide production
Authors: Eneko Sebastian-Garate, Bruna F. Gonçalves, Jordi Llusar, Pawel Gluchowski, Ivan Infante, Senentxu Lanceros-Mendez, Qi Zhang, Hugo Salazar
Reference: Nano Energy, 146, 111551, 2025
