J. Mater. Sci. Technol. ›› 2022, Vol. 104: 155-162.DOI: 10.1016/j.jmst.2021.07.014

• Research Article • Previous Articles     Next Articles

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

Songcan Wanga,*(), Yuelin Lia,b, Xin Wanga, Guohao Zia,b, Chenyang Zhoua,b, Boyan Liua, Gang Liud,e, Lianzhou Wangc,*(), Wei Huanga,*()   

  1. aFrontiers Science Center for Flexible Electronics, Xi’an Institute of Flexible Electronics (IFE), Xi’an Institute of Biomedical Materials & Engineering, Northwestern Polytechnical University, 127 West Youyi Road, Xi’an 710072, China
    bHonors College, Northwestern Polytechnical University, 127 West Youyi Road, Xi’an 710072, China
    cNanomaterials Centre, School of Chemical Engineering and Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, QLD 4072, Australia
    dShenyang National Laboratory for Materials Science, Institute of Metal Research Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, China
    eSchool of Materials Science and Engineering, University of Science and Technology of China, 72 Wenhua Road, Shenyang 110016, China

Abstract:

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 µmol 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.

Key words: Carbon nitride, Supramolecular preorganization, Hall mobility, Na doping, Solar hydrogen