Amorphous Carbon and Cyano-Group Self-Modified P-Doped g-C3N4 for Boosting Photocatalytic H2 Evolution

Designing g-C3N4-based nanostructured photocatalysts is crucial to boosting their application in advancing clean energy and sustainable environmental solutions. In this study, cyano groups and amorphous carbon self-modified P-doped g-C3N4 (PCNx) photocatalysts were designed and prepared by one-pot calcination. Melamine phosphate was employed as a multifunctional precursor to simultaneously achieve P-doping and amorphous carbon/cyano group self-modification in the g-C3N4 photocatalyst. The molar ratio of urea to melamine phosphate regulates the content of amorphous carbon and cyano groups, which further enhances the conductivity of g-C3N4. Due to the high conductivity of amorphous carbon and cyano groups, the charge transfer process was further accelerated. As a result, the optimized P-doping and amorphous carbon/cyano-group in PCN2 photocatalyst led to an excellent H2 production rate of 157.86 µmol·g−1·h−1 under visible light, which is approximately 2.4 times and 3 times higher than those of CN and PCN. The work developed an alternative strategy for the construction of highly efficient g-C3N4-based photocatalysts.