Construction of a dual Z-scheme Cu|Cu2O/TiO2/CuO photocatalyst composite film with magnetic field enhanced photocatalytic activity

A novel dual Z-scheme Cu|Cu 2 O/TiO 2 /CuO photocatalyst composite film is successfully prepared through chemical oxidation, in situ growth, sol–gel spin coating and high temperature calcination methods. The photocatalytic activity of composite film under simulated sunlight irradiation is obviously enhanced in external magnetic field in norfloxacin degradation with concurrent hydrogen production. This work hopefully opens up a new idea for improving the photocatalytic efficiency. • A novel dual Z-scheme Cu|Cu 2 O/TiO 2 /CuO photocatalyst composite film is first prepared. • The separation efficiency of carriers is improved due to presence of magnetic field. • The magnetic field accelerates electron transfer and enhances hydrogen production. • The photocatalytic activity enhancement is first explained by using electromagnetism. In this work, a novel dual Z-scheme Cu|Cu 2 O/TiO 2 /CuO photocatalyst composite film is successfully prepared through chemical oxidation, in-situ growth, sol–gel spin coating and high temperature calcination methods. Ulteriorly, a succession of characterizations are used to analyze composition and morphology of this photocatalyst composite film. The photocatalytic activity of photocatalyst composite film in an external magnetic field under simulated sunlight irradiation is evaluated via norfloxacin degradation with concurrent hydrogen production. Further, when dual Z-scheme Cu|Cu 2 O/TiO 2 /CuO photocatalyst composite film and fixed magnetic field occur relative rotation in a clockwise direction, inductive electromotive force is produced to accelerate the electron flow, promoting the separation efficiency of electron-hole pairs. Therefore, the efficiencies of photocatalyst composite film on norfloxacin degradation with simultaneous hydrogen production have been improved compared with that without magnetic field. In addition, the active species in norfloxacin degradation are explored by trapping experiment and electron spin resonance test. In the meanwhile, the possible mechanism of magnetic field assisted photocatalytic experiments performed by dual Z-scheme Cu|Cu 2 O/TiO 2 /CuO photocatalyst composite film is proposed. Finally, the possible role of induced electromotive force in inhibiting electron-holes recombination is proposed, which hopefully opens up a new idea for improving the photocatalytic efficiency based on external magnetic field.