Structure defects promoted exciton dissociation and carrier separation for enhancing photocatalytic hydrogen evolution

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journal

3 Scopus Citations
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Author(s)

  • Tianqi Wang
  • Qun Zhang
  • Po Keung Wong

Related Research Unit(s)

Detail(s)

Original languageEnglish
Article number118480
Journal / PublicationApplied Catalysis B: Environmental
Volume264
Online published28 Nov 2019
Publication statusPublished - 5 May 2020

Abstract

Structure defect poor and rich graphitic carbon nitrides (g-C3N4) were successfully prepared to disclose the relationships between structure defects and the exciton/carrier behaviors. The partial loss of the heptazine units in the matrix was the origin of the intrinsic structure defects in the g-C3N4, evidenced by the X-ray photoelectron spectroscopic analysis. Both the fluorescence and ultrafast transient absorption analyses demonstrated that the presence of the intrinsic structure defects within g-C3N4 promoted the dissociation of excitons and the separation of photogenerated carriers, reflected by the accelerated relaxation of the excited electrons from conduction band to the trap states and the prolonged relaxation of trapped electrons to the valence band. Thus, the structure defect rich g-C3N4 performed better in photocatalytic hydrogen production than structure defect poor g-C3N4. This study not only disclosed the influences of the intrinsic structure defects on exciton/carrier behaviors, but also provide an alternative perspective to modify the semiconductors for photocatalytic applications.

Research Area(s)

  • Carrier separation, Exciton dissociation, Graphitic carbon nitride, Structure defects

Citation Format(s)

Structure defects promoted exciton dissociation and carrier separation for enhancing photocatalytic hydrogen evolution. / Sun, Hongli; Wei, Kang; Wu, Dan; Jiang, Zhifeng; Zhao, Hui; Wang, Tianqi; Zhang, Qun; Wong, Po Keung.

In: Applied Catalysis B: Environmental, Vol. 264, 118480, 05.05.2020.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journal