Mesoporous graphitic carbon nitride (g-C3N4) nanosheets synthesized from carbonated beverage-reformed commercial melamine for enhanced photocatalytic hydrogen evolution

Abstract

The application of templating and etching agents for the synthesis of mesoporous graphitic carbon nitride (mpg-C₃N₄) is not environmentally friendly, motivating attempts to develop a green and efficient strategy to construct mpg-C₃N₄ with improved photocatalytic performance. Herein, for the first time, we demonstrate a general carbonated beverage-assisted hydrothermally-reformed commercial melamine (MA) strategy for the synthesis of mpg-C₃N₄ nanosheets. Although the dosage of carbonated beverage (including Coca-Cola, Pepsi-Cola, Sprite and Fanta) is very small for the modification of MA precursors, the improvement in the photocatalytic activity of the mpg-C₃N₄ products is very remarkable. With the unique structural advantages for aligned energy bands and charge carrier migration, and numerous photocatalytic sites, the visible-light-driven photocatalytic hydrogen evolution rate (HER) of mpg-C₃N₄ nanosheets synthesized from a Coca-Cola-reformed MA precursor is 15.1 times higher than that of bulk g-C₃N₄, achieving an apparent quantum yield of 7.7% at 420 nm. Similarly, mpg-C₃N₄ nanosheets synthesized from Pepsi-Cola-, Sprite- and Fanta-reformed MA precursors also exhibit enhanced photocatalytic HERs.