Heterostructured boron doped nanodiamonds@g- G_3N_4 nanocomposites with enhanced photocatalytic capability under visible light irradiation

摘要

Boron doped nanodiamonds (BDND) were coupled with graphitic carbon nitride (g-C3N4) nanosheets to form a heterojunction via a facile pyrolysis approach. The BDND@g-C3N4 heterojunction exhibits enhanced visible-light absorbance, improved charge generation/separation efficiency and prolonged lifetime of carriers, which lead to the enhanced photocatalytic activities for the hydrogen evolution and organic pollution under visible-light irradiation. The optimal H-2 evolution rate and apparent quantum efficiency at 420 nm of the BDND@g-C3N4 heterojunction is 96.3 mu molh(-1) and 6.91%, which is about 5 and 2 times higher than those of pristine g-C3N4 nanosheets (18.2 mu mol h(-1) and 3.92%). No obvious decrease in hydrogen generation rate is observed in the recycling experiment due to the high photo-stabilization of the BDND@g-C3N4 composite. The degradation kinetic rate constant of organic pollution of the BDND@g-C3N4 structure is 0.1075 min(-1,) which is 3 times higher compared to pristine g-C3N4. This work may provide a promising route to construct highly efficient non-metal photocatalysts for hydrogen evolution and organic pollution degradation under visible light irradiation. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.