Self-surface-passivation of titanium doped hematite photoanode for efficient solar water and formaldehyde oxidation

Abstract

Herein, we present a new and available Ti doping and surface self-passivation strategy to significantly boost the PEC performance of the Fe2O3 nanorods for both solar water splitting and formaldehyde (HCHO) oxidation. Upon Ti doping and surface passivation with KOH treatment, the self-passived Ti4+ doped Fe2O3 nanorods exhibit substantially higher PEC performance compared to the pristine Fe2O3 and Ti4+ doped Fe2O3 nanorods, achieving a remarkable photocurrent of 3.7mAcm−2 at 1.5V vs. RHE. Furthermore, these self-passived Ti4+ doped Fe2O3 nanorods also show a 100mV cathodic shift in onset potential than that of Ti4+ doped Fe2O3 nanorods and excellent durability. Such the substantially improved photoelectrochemical performance is ascribed to the dramatically increased donor densities and reduced electron-hole recommendation as a result of Ti doping and surface passivation layer that formed after KOH treatment.