The application of FTO-Cu 2 O/Ag 3 PO 4 heterojunction in the photoelectrochemical degradation of emerging pharmaceutical pollutant under visible light irradiation.

We report the photoelectrochemical application of a visible light active FTO-Cu ₂ O/Ag ₃ PO ₄ 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 Cu ₂ O/Ag ₃ PO ₄ interface. The highest photocurrent response of 0.62 mAcm ^-2 was obtained for the composite photoanode which was four times higher than pure Cu ₂ O and about three times higher than pristine Ag ₃ PO ₄ . 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-Cu ₂ O/Ag ₃ PO ₄ 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.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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