Photoelectrochemical properties of FTO/p-NiO electrode induced by UV light irradiation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Photoelectrochemical properties of p-nickel oxide (NiO) thin film deposited on fluorine-doped tin oxide (FTO) electrode, by combination of co-precipitation in aqueous media along with the dip-coating process, were investigated by cyclic voltammetry and chronoamperometry techniques in sodium sulfate (Na2SO4) electrolyte solution. The electrochemical characterization measurements have shown that the FTO/p-NiO electrode presents sensitivity to UV light, as observed by the increased photo-induced current, exposed to a more negative potential. The photoelectrochemical parameters obtained were photocurrent response time (a dagger t (1)), photocurrent decay time (a dagger t (0)), and photocurrent density stability (j (ph), j (light on) -aEuro parts per thousand j (light off)). Besides, this electrode shows excellent performance for methylene blue degradation under UV light irradiation condition, with estimated k (obs) value of 170 x 10(-4) min(-1), which is nine times higher than the dark condition and about three times higher than NiO powder catalyst. Results presented here allow concluding that the p-NiO thin film stands as an important electrode material with technological potential to be used directly in environmental preservation.