Necklace-like hybrid nanofiber as an enhanced and recyclable intrinsic photocatalyst for tetracycline removal and hydrogen evolution

Recycling of nanophotocatalyst in slurry system is still a challenge due to its powder form. Here, polyacrylonitrile with nanophotocatalyst (CdS, Cd@TiO2, and CdS@void@TiO2, respectively) and vanadyl acetylacetonate as a potential oxidant was electrospun into nanofiber membrane. After sintering and acidification, polypyrrole (PPy) was coated via V5+ oxidation polymerization, and the necklace-like nanofiber photocatalyst (nanophotocatalyst@PPy NFs) was yielded. After calcination and PPy covering, nanophotocatalyst@PPy NFs with ternary heterojunctions have the narrow energy gap of ~1.6 eV and broad response in UV and visible light region. The maximum removal efficiency of the nanophotocatalyst@PPy NF can reach up to ~77% for tetracycline, and H2 evolution rate raises up to 654.7 μmol h−1 g−1. With the protection of PPy covering, nanophotocatalyst@PPy NFs possess outstanding resistance to photocorrosion. As a recyclable fiber-form photocatalyst, our nanophotocatalyst@PPy NFs with commendable photocatalytic activity and stable performance as well as easy handling and recycling show great promise for environmental remediation.