One-pot fabrication of BiPO4/Bi2S3 hybrid structures for visible-light driven reduction of hazardous Cr(VI)

R A Geioushy; S M El-Sheikh; Ahmed B Azzam; Bahaa Ahmed Salah; Farida M El-Dars

doi:10.1016/j.jhazmat.2019.120955

One-pot fabrication of BiPO₄/Bi₂S₃ hybrid structures for visible-light driven reduction of hazardous Cr(VI)

J Hazard Mater. 2020 Jan 5:381:120955. doi: 10.1016/j.jhazmat.2019.120955. Epub 2019 Aug 4.

Authors

R A Geioushy¹, S M El-Sheikh², Ahmed B Azzam³, Bahaa Ahmed Salah³, Farida M El-Dars³

Affiliations

¹ Nanomaterials and Nanotechnology Department, Advanced Materials Division, Central Metallurgical R & D Institute (CMRDI), P.O. Box, 87, Helwan, 11421, Cairo, Egypt. Electronic address: r_gushy@yahoo.com.
² Nanomaterials and Nanotechnology Department, Advanced Materials Division, Central Metallurgical R & D Institute (CMRDI), P.O. Box, 87, Helwan, 11421, Cairo, Egypt. Electronic address: selsheikh2001@gmail.com.
³ Chemistry Department, Faculty of Science, Helwan University, Helwan, Egypt.

PMID: 31412306
DOI: 10.1016/j.jhazmat.2019.120955

Abstract

For the first time, a novel BiPO₄/Bi₂S₃ heterostructures with different morphologies have been fabricated through a facile and rapid one pot precipitation route followed by anion-exchange strategy for the photoreduction of toxic Cr(VI) to harmless Cr (III). The hybrid structures systematically investigated using XRD, FE-SEM, EDS, TEM, HRTEM, XPS, FT-IR, UV-vis DRS, and PL. Changing the solvent type has a significant role for controllable morphologies of BiPO₄/Bi₂S₃ hybrid as well as the catalytic activity. The BiPO₄/Bi₂S₃ hybrid synthesized in diethylene glycol (DEG) performed the highest reduction efficiency of Cr(VI) within 20 min, compared with pure hexagonal phase of BiPO₄ under visible light. The rate constant for BiPO₄/Bi₂S₃ synthesized in DEG found to be 20.3 times larger than that for pure BiPO₄. In addition, the presence of tartaric acid as hole scavenger could enhance the Cr(VI) reduction efficiency to 97.9%. No significant decrease in the catalytic efficiency after recycling up to four cycles. This promising study could present a significant approach towards Cr(VI) photoreduction from water through the novel BiPO₄/Bi₂S₃ photocatalyst.

Keywords: BiPO(4)/Bi(2)S(3) heterostructures; Cr(VI) reduction; Photocatalyst; Visible light.