Multi‐Electric Field‐Enhanced CuInS ₂ ‐Modified TiO ₂ (Anatase)/TiO ₂ (Rutile)/PVDF Nanofiber Membrane for Multifunctional Piezo‐Photocatalysis

Abstract Coupling device of reasonable microarchitecture, component control, and multi‐electric fields to efficiently separate and rapidly transfer charges by using multiple driving forces and charge transfer channels is an outstanding strategy for addressing water pollution and the energy crisis. Self‐supporting multi‐electric fields collaborative CuInS ₂ nanocubes modified TiO ₂ (Anatase)/TiO ₂ (rutile)/Polyvinylidene fluoride (PVDF) (named as CuTi(AR)P) double S‐scheme heterojunction nanofibre membrane piezoelectric photocatalyst is designed and constructed. The dispersion of TiO ₂ with different crystalline phases in 1D PVDF nanofibres ensures sufficient photo‐generated carrier generation and rapid migration. Furthermore, the vertical growth of 3D CuInS ₂ nanocubes on the surface of 1D nanofibres provides a large specific surface area and broadens the light‐response range. The hierarchical band arrangement of four different functional components utilized enables the multi‐electric fields synergy to be formed through the internal‐electric fields (Double S‐scheme heterojunction) and piezoelectric field (PVDF), greatly reducing the possibility of charge recombination. By means of the synergies of energy‐band engineering, nanostructure interface and broadening spectrum design, the piezo‐photocatalytic efficiencies of 0.50CuTi(AR)P for Cr(VI) reduction, ciprofloxacin degradation, hydrogen and H ₂ O ₂ production reach respectively as high as 100.00% (60 min), 94.30% (50 min), 893.3 and 1174.7 µmol h ⁻¹ g ⁻¹ under stirring united with simulated sunlight exposure, realizing multifunctional characteristics.