A highly ordered honeycomb-like nickel(III/II) oxide-enhanced photocatalytic fuel cell for effective degradation of bisphenol A.

The honeycomb-like nickel(III/II) oxide interpenetrated framework arrays labelled as H-NiOx are used as cathode catalysts for the degradation of bisphenol A (BPA) in visible light-excited fuel cells. The nanoparticle close-packed NiOx aggregates (C-NiOx) and H-NiOx are prepared by conventional electrodeposition (ED) and advanced oxidation-associated electrodeposition (AO-ED) strategies, carried out by multiple voltammetry controlled in the potential ranges of 0 to -1.3 V and 1.3 to -1.3 V (vs. SCE), respectively. Compared with C-NiOx, the H-NiOx frameworks with smaller charge transfer resistance and higher surface-confined redox-active centers exhibit larger cathode electrocatalytic activity for the photocatalytic degradation of BPA. The NaClO can act as a sacrificial agent to sustain the integrity and stability of H-NiOx cathode. The H-NiOx-assisted BPA degradation conditions are optimized by changing process variables. The BPA is degraded by 48.5% within 120 min in photocatalytic BPA (1.0 mmol L-1, pH 13) fuel cell employing H-NiOx cathode, CdS/TiO2 photoanode and 0.2 mol L-1 NaClO catholyte, and its degradation rate conforms to the first-order reaction kinetic model. The H-NiOx can remarkably enhance the performances of the photocatalytic fuel cell, achieving a 4.1-fold or 15.2-fold increase in the short circuit current and maximum power density compared with that using bare cathode.