Theoretical and experimental investigation on electronic and photocatalytic properties of n-p BiOBr/FeWO₄ heterojunction for dyes degradation

Author(s):Show less -

Silva, Leticia M. B. ; Barros, Francisco A. A. ; Oliveira, Marisa C. ; Ribeiro, Renan A. P. ; da Costa, M. E. H. Maia ; Alves, Odivaldo C. ; Santos, Evelyn C. S. ; Souza, Luiz K. C. de ; Santos, C. C. ; de Menezes, A. S. ; Sharma, Surender K. ; Luz Jr, Geraldo E. ; Cavalcante, L. S. ; Longo, E. ; Almeida, M. A. P.

• Document type: Journal article
• Source: Journal of Alloys and Compounds; v. 1010, p. 18-pg., 2025-01-05.

Abstract

The present work reports novel n-p BiOBr/FeWO4 heterojunctions designed for proficient photodegradation of methyl orange and rhodamine B dyes. The structural and microstructural features confirm the realization of soft interface between BiOBr/FeWO4 phase with large number of singly ionized oxygen vacancies ((center dot)(O)) as validated through electron paramagnetic resonance spectroscopy, which spectacle a significant role in the formation of electron (e(-)) <-> hole(h(+)) pairs in the heterojunction. Photocatalytic tests exhibit outstanding improvement in the photocatalytic activity for heterojunctions in relation to pristine BiOBr and FeWO4 phases. Moreover, we have performed scavengers experiments viz., benzoquinone, isopropyl alcohol, and sodium ethylenediaminetetraacetate, where the superoxide and hydroxyl radicals were mainly responsible for the degradation of the methyl orange and rhodamine B dye. Finally, the theoretical calculations at the density functional theory level confirmed the presence of surface defects related to V-O(center dot) at BiOBr/FeWO4 heterojunctions, responsible to control the electronic structure and adsorption features of the interface. We establish that the V-O(center dot) on the surface play a significant role in reducing the e(-)<-> h(+) recombination rates(,) and the captured e(-) can be used to form radical oxygen's species, which also contributing to improve the overall photocatalytic performance. (AU)

• FAPESP's process: 21/01651-1 - CDMF - Functional Materials Development Center: theoretical study of multifunctional materials with potential antiviral application
• Grantee: Marisa Carvalho de Oliveira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral