Research of the preparation of carbon-doped pg-C3N4 and its photocatalytic performance

Abstract

In order to improve the photocatalytic activity of a single semiconductor material, porous graphite phase carbon nitride (pg-C3N4) with high specific surface area was prepared by hydrothermal method. Then pg-C3N4 was modified by carbon doping and gold nanoparticles (AuNPs) loading to obtain Au/pg-C@C3N4 composite nanomaterials. The composition, microstructure and properties of the composites were characterized. The results show that the introduction of carbon element does not destroy the original lamellar structure of the pg-C3N4, but significantly improves the specific surface area of pure pg-C3N4 (up to 158.2 m2/g). By introducing AuNPs into the matrix, the plasmon resonance effect of nanometals can be used to improve the absorption of visible light and the separation efficiency of photo generated electron-holes. It shows that when the AuNPs concentration is 0.5% (mass fraction), the nanocomposite has the highest photocatalytic performance (apparent reaction rate constant k=0.078 4 s-1). Therefore, the study on the preparation of composite photocatalyst with high activity by carbon doping and gold nanoparticle loading to modified pg-C3N4 provides a theoretical basis for further improving the catalytic activity of carbon nitride-based catalysts in the future.

Keywords

• polymer composites; porous graphitic carbon nitride; carbon doping; au nanoparticles; photocatalytic performance; mechanism