Engineering of reduced graphene oxide on nanosheet–g-C₃N₄/perylene imide heterojunction for enhanced photocatalytic redox performance

Liping YANG, Pengyuan WANG, Jiao YIN, Chuanyi WANG, Guohui DONG, Yuanhao WANG, Wing Kei HO

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2 Citations (Scopus)

Abstract

g-C₃N₄-based photocatalysts are recognized as promising candidates for photocatalytic purification of air and solar energy conversions; but their practical application is still limited by the sluggish charge transfer dynamic. Herein, a Z-scheme ternary heterojunction (nanosheet–g-C₃N₄ [NCN]/perylene imide [PI]/reduced graphene oxide [rGO], NCN/PI/rGO) was successfully constructed. For experimental comparison, NCN/rGO/PI was concurrently synthesized through different reaction sequences. In these ternary heterojunction systems, the introduction order of rGO affects the morphology structure and the interaction between phases and results in two diverse electron transfer modes which determine the different photocatalytic redox performances. The as-obtained NCN/PI/rGO Z-scheme heterostructure exhibited superior photocatalytic activity towards the photocatalytic removal of NO and generation of H₂O₂ under visible light irradiation. Such photocatalytic activity was about 1.58 and 1.23 times higher than those of NCN and NCN/PI, respectively, in NO removal. Such enhanced photocatalytic properties can be ascribed to the two-step electron transfer process involving the CB electrons in PI combined with the VB holes of NCN via the Z-scheme pathway (process I, PI→NCN) because PI was grown in situ on the NCN through thermal condensation polymerisation. This process enabled intimate contact between NCN and PI and a short charge-transfer distance. The residual electrons in the CB of NCN then flowed into the rGO (process II, PI→NCN→RGO). Thus, the simultaneous occurrence of two electron transfers processes I and II help improve the photocatalytic activity. Constructing NCN/PI/rGO Z-scheme heterostructures is anticipated to be an effective strategy for developing high-performance photocatalysts that facilitate the utilisation of solar energy. Copyright © 2019 Elsevier B.V. All rights reserved.
Original languageEnglish
Pages (from-to)42-51
JournalApplied Catalysis B: Environmental
Volume250
Early online dateMar 2019
DOIs
Publication statusPublished - Aug 2019

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Perylene
Imides
Graphite
Oxides
Graphene
Heterojunctions
oxide
engineering
electron
Electrons
Photocatalysts
Solar energy
Charge transfer
Polycondensation
Energy conversion
polymerization
Purification
purification
Oxidation-Reduction
condensation

Bibliographical note

Yang, L., Wang, P., Yin, J., Wang, C., Dong, G., Wang, Y., & Ho, W. (2019). Engineering of reduced graphene oxide on nanosheet–g-C₃N₄/perylene imide heterojunction for enhanced photocatalytic redox performance. Applied Catalysis B: Environmental, 250, 42-51. doi: 10.1016/j.apcatb.2019.02.076

Keywords

  • Z-Scheme ternary heterojunction
  • rGO
  • PTCDI
  • g-C₃N₄photocatalytic NO removal