MOF–derived hollow porous ZnFe2O4/AgCl/Ag/C nanotubes with magnetic–dielectric synergy as high–performance photocatalysts for hydrogen evolution reaction

Abstract The design of unique structures for semiconductor photocatalysts is one of the most effective approach to stimulate their performance toward solar–to–chemical energy conversion. Herein, an interesting scheme has been introduced to produce hollow porous ZnFe2O4/AgCl/Ag/C nanotubes on the PDA@PANI nanofibers by a simple combined PANI capturing–PDA embedding–in situ graphitization process. In a first step, PDA@PANI were first prepared via a coaxial electrospinning process, followed by PANI capturing transition metal ions (Zn2+ and Fe2+) with the assistance of 2,5–dihydroxy–1,4–benzenedicarboxylic acid to convert these metal ions into PDA@PANI@MOF–74–Zn/Fe through thermal treatment. Then, AgCl cubes and Ag NPs were synthesized via in–situ embedding with various active groups of the PDA and its reducibility. At last, after calcination of the PDA@PANI@MOF–74–Zn/Fe/AgCl/Ag, ZnFe2O4/AgCl/Ag/C nanotubes with uniform distribution of graphitic carbon were successfully fabricated. Benefiting from the novel hollow porous structure, the obtained ZnFe2O4/AgCl/Ag/C exhibited outstanding H2 evolution activity (e.g., 7524 µmol h−1 g−1) and high stability without engaging any cocatalyst, which is among the highest reported for ZnFe2O4–based materials with different morphologies and nanostructures.