Three-dimentional (3D) Bi 2 O 3-BiOI heterojunction was fabricated on the basis of Bi 2 O 3 film by a simple dipping method at room temperature. The as-prepared film samples were characterized by scanning electron microscope (SEM), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV-Vis DRS spectra. Results indicated that BiOI nanosheets with cross-flake arrays were formed via in situ etching and exchanging of Bi 2 O 3 layer by Iin KI aqueous solution, which grow around the residual Bi 2 O 3 particles to form 3D Bi 2 O 3-BiOI heterojunction. Liner sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) Nyquist plots and incident monochromatic photon-to-current conversion efficiency (IPCE) indicated that easier generation, separation and transfer of photogenerated charges were achieved on the special 3D heterojunction. The photocurrent density of the 3D Bi 2 O 3-BiOI composite increased by 8.4 times relative to pure Bi 2 O 3 at 0.35 V vs. Ag/AgCl in 0.2 M Na 2 SO 4 aqueous solution under visible light irradiation. For the PEC degradation of phenol, the composite film also exhibited greatly enhanced activity. The calculated rate constant was 3.8 times that on pure Bi 2 O 3. Furthermore, good stability in long-time photocurrent and cyclic degradation of phenol can both be observed, indicating that the 3D Bi 2 O 3-BiOI film can be potentially applied in water oxidation and environmental remediation.

Ternary Fe2O3–MoS2–Cu2O nanocomposites were fabricated via electrodeposition and hydrothermal method. The as-prepared photocatalytic films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The results indicated that MoS2 and Cu2O particles were successfully deposited onto the surface of Fe2O3 particles. MoS2 and Cu2O coloading achieved a synergetic effect on the improvement of the photoelectrochemical performance of Fe2O3 film. The highest photocurrent density was achieved on Fe2O3–MoS2–Cu2O film, which was 20, ∼5.5, and 2 times those of Fe2O3, Fe2O3–MoS2, and Fe2O3–Cu2O films, respectively. The excellent photoelectrocatalytic performance was attributed to the Z-scheme electron transfer mechanism, which results in the fast charge transfer and strong redox ability on the ternary composite. This work provides a promising Z-scheme ternary semiconductor for environmental purification and water oxidation.

A novel nitrogen removal strategy, the combined photoelectrocatalytic oxidation and autotrophic biofilm denitrification, was developed to achieve simultaneous NH 4