The application of FTO-Cu2O/Ag3PO4 heterojunction in the photoelectrochemical degradation of emerging pharmaceutical pollutant under visible light irradiation

Babatunde A Koiki; Benjamin O Orimolade; Busisiwe N Zwane; Oluchi V Nkwachukwu; Charles Muzenda; Duduzile Nkosi; Omotayo A Arotiba

doi:10.1016/j.chemosphere.2020.129231

The application of FTO-Cu₂O/Ag₃PO₄ heterojunction in the photoelectrochemical degradation of emerging pharmaceutical pollutant under visible light irradiation

Chemosphere. 2021 Mar:266:129231. doi: 10.1016/j.chemosphere.2020.129231. Epub 2020 Dec 6.

Authors

Babatunde A Koiki¹, Benjamin O Orimolade¹, Busisiwe N Zwane², Oluchi V Nkwachukwu¹, Charles Muzenda¹, Duduzile Nkosi¹, Omotayo A Arotiba³

Affiliations

¹ Department of Chemical Sciences, University of Johannesburg, South Africa.
² Department of Chemical Sciences, University of Johannesburg, South Africa; DST/Mintek Nanotechnology Innovation Centre, University of Johannesburg, South Africa.
³ Department of Chemical Sciences, University of Johannesburg, South Africa; Centre for Nanomaterials Science Research, University of Johannesburg, South Africa. Electronic address: oarotiba@uj.ac.za.

PMID: 33307414
DOI: 10.1016/j.chemosphere.2020.129231

Abstract

We report the photoelectrochemical application of a visible light active FTO-Cu₂O/Ag₃PO₄ photoanode for the abatement of sulfamethoxazole in water. The as-synthesised photoanodes were characterised using XRD, field emission SEM, EDX, diffuse reflectance UV-vis, impedance spectroscopy and chronoamperometry. The results obtained confirmed a successful formation of p-n heterojunction at the Cu₂O/Ag₃PO₄ interface. The highest photocurrent response of 0.62 mAcm^-2 was obtained for the composite photoanode which was four times higher than pure Cu₂O and about three times higher than pristine Ag₃PO₄. The photoanode gave 67% removal efficiency within 2 h upon its photoelectrochemical application in the degradation of sulfamethoxazole with 1.5 V bias potential at pH 6.2. The FTO-Cu₂O/Ag₃PO₄ electrode was also applied in the treatment of a cocktail of synthetic organics containing sulfamethoxazole and orange II dye. The photogenerated holes was found to be the major oxidant and the photoanodes was stable and reusable.

Keywords: Photoanode; Photoelectrochemical degradation; Silver phosphate; Sulfamethoxazole; copper(I) oxide; p-n heterojunctions.

MeSH terms

Catalysis
Environmental Pollutants*
Light
Pharmaceutical Preparations*
Silver

Substances

Environmental Pollutants
Pharmaceutical Preparations
Silver