Structural engineering of g-C3N4 nanosheets via creatinine-mediated post-polymerization calcination for boosted photocatalytic hydrogen production and organic pollutants degradation

A creatinine-mediated post-polymerization calcination approach has been developed for modifying g-C 3 N 4 nanosheets to enhance their photocatalytic hydrogen production and pollutant degradation activities. The incorporation of creatine or its derivatives induced a negative shift in the conduction and valence band edges of g-C 3 N 4 and activated n-π ⁎ electronic transition, thereby enhancing the reducing ability of electrons and extending light absorption range. Creatinine-calcined g-C 3 N 4 (TCN-30Crn) exhibited a significantly enhanced photocatalytic activity toward hydrogen production (3721.9 μmol h −1 g −1 ) in water, which was 8.6 times that of the pristine counterpart. The hydrogen production rate was further increased to 8853.67 μmol h −1 g −1 in aqueous solution of sodium dihydrogen phosphate. TCN-30Crn also showed broad catalytic activity for the photodegradation of methyl orange, rhodamine B, o -nitroaniline, methylene blue, and ciprofloxacin. The high activity of creatinine-calcined g-C 3 N 4 could be attributed to the improved separation efficiency of photo-generated electron-hole pairs and the inhibition of charge carriers recombination.