Jump to main content
Jump to site search


Unveiling the role of tetragonal BiVO4 as a mediator for dual phase BiVO4/g-C3N4 composite photocatalysts enabling highly efficient water oxidation via Z-scheme charge transfer

Author affiliations

Abstract

Monoclinic scheelite BiVO4 (BVO-M) based materials are of great interest as photocatalysts for water oxidation essential to produce value-added chemical fuels, but their slow charge transfer and low activity are yet to be resolved. As a solution to overcome this challenge, we report Z-scheme photocatalyst fabricated by integrating the dual phase structure of monoclinic scheelite and tetragonal zircon-type BiVO4 (BVO-T) moieties with graphitic carbon nitride (g-C3N4) having π-conjugated two dimensional layers suited to visible light-induced charge transfer. Moreover, V K-edge and Bi L3-edge X-ray absorption near-edge structure (XANES) and Fourier transformed extended X-ray absorption fine structure (EXAFS) spectra demonstrate that the tetragonal zircon-type BiVO4 structures in a Z-scheme catalyst form a bridge between BVO-M and g-C3N4 structures so that it acts as an electron mediator to accelerate charge transfer, in agreement with the zeta-potential analysis and the band structure revealed by UV-vis spectroscopy and ultraviolet photoelectron spectroscopy analyses. Furthermore, a Z-scheme photocatalyst is exhibited to show a 3-fold longer charge carrier lifetime than BVO-M, thereby enabling the greater than three-fold enhancement in photocatalytic water oxidation activity. Additionally, isotope 18O-labelling experiments reveal that evolved oxygen molecules result from water through photocatalytic water oxidation.

Graphical abstract: Unveiling the role of tetragonal BiVO4 as a mediator for dual phase BiVO4/g-C3N4 composite photocatalysts enabling highly efficient water oxidation via Z-scheme charge transfer

Back to tab navigation

Supplementary files

Publication details

The article was received on 27 Sep 2019, accepted on 04 Nov 2019 and first published on 05 Nov 2019


Article type: Communication
DOI: 10.1039/C9TA10704E
J. Mater. Chem. A, 2019, Advance Article

  •   Request permissions

    Unveiling the role of tetragonal BiVO4 as a mediator for dual phase BiVO4/g-C3N4 composite photocatalysts enabling highly efficient water oxidation via Z-scheme charge transfer

    H. J. Kong, K. Kim, S. Kim, H. Lee and J. K. Kang, J. Mater. Chem. A, 2019, Advance Article , DOI: 10.1039/C9TA10704E

Search articles by author

Spotlight

Advertisements