Tailoring the Morphology of g-C3N4 by Self-Assembly towards High Photocatalytic Performance

Graphical Shaping graphitic nitrides: Synthesis of graphitic carbon nitride (g-C 3 N 4 ) and tailoring of its morphology was performed through adjustment of the molar ratio of melamine to urea, their self-assembly by hydrogen bonding and ionic interactions, and calcination. We report a novel method for the preparation of graphitic carbon nitride (g-C 3 N 4 ) with various morphologies through self-assembly and calcination, which starts from the raw materials melamine, urea, and cyanuric acid. The hollow to wormlike morphologies of g-C 3 N 4 could be readily tailored by adjusting the molar ratio of melamine to urea; with increase in the molar ratio from 3:1 to 1:3, a morphology transformation was observed. The morphologies were tailored by self-assembly of the aggregates by hydrogen bonding and ionic interactions. Correspondingly, an increased BET surface area from 49.6 to 97.4 m 2 g −1 was observed. If used as a photocatalyst in degrading rhodamine B (RhB) under visible-light irradiation, these g-C 3 N 4 samples demonstrated 7 to 13 times higher performance than conventional bulk g-C 3 N 4 . The high performance was attributed to the unique morphology that provided not only high specific surface area but low recombination losses of photogenerated charges.