One-step supramolecular preorganization constructed crinkly graphitic carbon nitride nanosheets with enhanced photocatalytic activity

Here we report a new one-step thermal polycondensation process to form crinkly graphitic carbon nitride nanosheets (CGCNNs) via supramolecular preorganization, using a mixture of urea and melamine as the starting material. Systematical studies reveal that the newly developed CGCNNs significantly strengthen the optical absorption, widen the bandgap, and increase the Hall mobility and carrier density compared to that of its bulk counterpart, regardless of the similar chemical composition and structure. As a result, the photocatalytic hydrogen production rate is improved by 7 times. Moreover, Na doping of CGCNNs can further promote its photocatalytic activity, leading to an excellent photocatalytic hydrogen production rate of 250.9 mu mol h -1 , which is approximately 10.5 times higher than its bulk counterpart. Moreover, an impressive apparent quantum efficiency of 19.12% is achieved at 420 nm. This study provides a facile strategy for the design of efficient low-cost carbon-nitride-based photocatalysts for solar fuel production. (c) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

A new one-step thermal polycondensation process is reported to produce crinkly graphitic carbon nitride nanosheets (CGCNNs) through supramolecular preorganization using a mixture of urea and melamine. Systematical studies show that the newly developed CGCNNs exhibit significantly enhanced optical absorption, widened bandgap, increased Hall mobility, and carrier density compared to its bulk counterpart, leading to a 7-fold improvement in photocatalytic hydrogen production rate. Na doping of CGCNNs further enhances its photocatalytic activity, resulting in an impressive hydrogen production rate approximately 10.5 times higher than its bulk counterpart, along with an apparent quantum efficiency of 19.12% at 420 nm.