In-situ growth of lepidocrocite on BiO rod: A perfect cycle coupling photocatalysis and heterogeneous fenton-like process by potential-level matching with advanced oxidation.

γ-FeOOH was grown in situ on the surface of rod BiO to construct a perfect cycle coupling photocatalysis and heterogeneous Fenton-like process. The degradation efficiency of this system was detected under the irradiation of visible light. γ-FeOOH/BiO showed better degradation efficiency than pure BiO and γ-FeOOH, and the amount of TOC was decreased to 4.3, suggesting that the system exhibits outstanding oxidation ability that MO and phenol could be degraded to CO and HO totally. PL spectra, trapping experiments and ESR test were also carried out to confirm the mechanism of photocatalysis with heterogeneous Fenton-like process, and the suitable conduction band (CB) of BiO matches the electric potential of iron ions was proved to be the key to keep the perfect cycle. Then optimal concentration of HO, the effect of pH and the stability of the photocatalyst were also investigated.