Which is the photocatalytic efficiency better the g-C3N4 on surface or carbon microspheres on surface in carbon microspheres/g-C3N4?

Abstract

Generally, surface property has an important effect on photocatalytic performance. For a composite photocatalyst g-C3N4/carbon microspheres (CN/CS), which photocatalytic efficiency is better the g-C3N4 on surface or carbon microspheres on surface? Herein, the sample of carbon microspheres on surface (CN/CS-Sur) and the sample of g-C3N4 loaded on the surface (CN/CS-In) were synthesized via thermal decomposition-hydrothermal method or hydrothermal-thermal decomposition, respectively. The photocatalytic rate of the CN/CS-Sur was 5 times that of the CN/CS-In, suggesting that the surface property played important role. The abound surface hydroxyl groups (–OH), which are were origin from the CS, improved the hydrophilicity and dispersibility of the CN/CS-Sur, and caused higher electrostatic adsorption to methylene blue (MB). Furthermore, the high electrical conductivity of CS accelerated the rate of charge transfer and suppressed the recombination of photocarriers. Our results suggest the assemble position evidently affect the surface property and the photocatalytic performance.