Electrospun self-supporting double Z-scheme tricolor-typed microfiber oriented-heterostructure photocatalyst with highly effective hydrogen evolution and organic pollutants degradation

Abstract

Energy shortage and environmental pollution have seriously threatened our environment, so it is urgent to develop efficient photocatalysts to solve these dilemmas. Here, we firstly designed and manufactured the self-supporting double Z-scheme [g-C3N4/polymethylmethacrylate (PMMA)]//[TiO2/polyaniline (PANI)/PMMA]//[self-assembled 3, 4, 9, 10-perylene tetraformyl diimide (PDI)/PMMA] tricolor-typed microfiber oriented-heterostructure photocatalyst (marked as TMOP) via a tri-axial parallel electrospinning. The optimized TMOP simultaneously manifests prominent hydrogen generation efficiency (536.7 μmol h−1 g−1) and splendid degradation rates for four different leuco antibiotics of ciprofloxacin (88.99%, 90 min), tetracycline hydrochloride (91.15%, 80 min), chlortetracycline hydrochloride (77.55%, 150 min), levofloxacin (69.51%,150 min) and colored dye methylene blue (92.50%, 50 min) under simulated sunlight illumination, validating perfect tri-functional features. The dramatically heightened photocatalytic activity of TMOP mainly benefits from the morphology, heterostructure and components of tricolor-typed microfiber, which not only increases the active sites, but also broadens the absorption range of solar spectrum by using the wide spectral characteristics of PDI. More importantly, the synergistic effect between conductive polyaniline and one-dimensional double Z-scheme oriented-heterostructures accelerates the oriented and rapid transmission of carriers in multiple paths, thus greatly reducing the possibility of carriers recombination and retaining the strong redox capacity of carriers. Additionally, TMOP with self-supporting feature presents remarkable recoverability. The construction mechanism of tricolor-typed microfiber and TMOP as well as double Z-schem preserving the strong redox capacity of carriers photocatalytic mechanism are advanced.