Photocatalytic properties of nanostructured g-C3N4 hollow microspheres decorated with OH-CQDs

Abstract

Hydroxylated carbon quantum dots (OH-CQDs) modified g-C₃N₄ hollow microspheres were prepared using a supramolecular precursor self-assembly method. The incorporation of OH-CQDs into the precursor resulted in the formation of a hollow flower-like microsphere structure composed of g-C₃N₄ nanoflakes in the final samples, which exhibited a morphology that was roughly inherited from that of the supramolecular precursor. The incorporation of an optimal quantity of OH-CQDs did not result in a deterioration of the g-C₃N₄ product morphology; rather, it led to an enhancement in its microsphere structure. The modified nanostructure of g-C₃N₄ resulted in a significant increase in reaction sites and promoted the adsorption of organic dye molecules on the surface of the g-C₃N₄ photocatalyst during degradation reactions. Furthermore, despite the reduction in carrier concentration of g-C₃N₄ resulting from the decoration with OH-CQDs, the impedance was significantly diminished and the photocurrent density was also markedly improved. It can thus be concluded that the decoration of OH-CQDs has significantly enhanced the mobility of g-C₃N₄, thereby contributing to the improvement of the photocatalytic performance of the g-C₃N₄ photocatalyst.