Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 5, 2015
Previous Article Next Article

Moderate band-gap-broadening induced high separation of electron–hole pairs in Br substituted BiOI: a combined experimental and theoretical investigation

Author affiliations

Abstract

We, for the first time, demonstrate band-gap-broadening as a new approach to remarkably enhance the photocatalytic activity of Br substituted BiOI photocatalysts, which were fabricated via a facile chemical precipitation route. The successful incorporation of Br ions into the crystal lattice of BiOI was confirmed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM). The photocatalytic experiments demonstrated that all of the Br–BiOI samples exhibited highly improved photocatalytic performances pertaining to rhodamine B (RhB) and phenol degradation under visible light (λ > 420 nm). The active species trapping and electron spin resonance (ESR) experiments also suggested that more superoxide radicals (˙O2), serving as the main active species, were generated over Br–BiOI than pristine BiOI in the photooxidation process. Based on the results from experiments and theoretical calculations, the enhancement of photocatalytic activity should be attributed to the lowered valence band (VB) potential and enlarged band gap induced by the Br replacement, which greatly facilitated the high separation of photoinduced electron–hole pairs, as verified by the photoluminescence (PL) experiments, electrochemical impedance spectra (EIS) and Bode-phase spectra. This work sheds light on a new method to improve the photocatalytic performance of photocatalysts.

Graphical abstract: Moderate band-gap-broadening induced high separation of electron–hole pairs in Br substituted BiOI: a combined experimental and theoretical investigation

Back to tab navigation

Supplementary files

Article information


Submitted
23 Oct 2014
Accepted
08 Dec 2014
First published
15 Dec 2014

Phys. Chem. Chem. Phys., 2015,17, 3673-3679
Article type
Paper

Moderate band-gap-broadening induced high separation of electron–hole pairs in Br substituted BiOI: a combined experimental and theoretical investigation

H. Huang, X. Li, X. Han, N. Tian, Y. Zhang and T. Zhang, Phys. Chem. Chem. Phys., 2015, 17, 3673
DOI: 10.1039/C4CP04842C

Social activity

Search articles by author

Spotlight

Advertisements