Palladium nanoparticles modified electrospun CoFe2O4 nanotubes with enhanced peroxidase-like activity for colorimetric detection of hydrogen peroxide

Abstract

Herein, we report a simple procedure to decorate small palladium nanoparticles (Pd NPs) on the surface of CoFe₂O₄ nanotubes; the decorated nanotubes possess intrinsic peroxidase-like activity for the sensitive detection of H₂O₂. The CoFe₂O₄ nanotubes are prepared via an electrospinning technique, followed by a calcination process in air. The functionalization of Pd NPs on the surface of CoFe₂O₄ nanotubes was achieved through an in situ reduction process using ascorbic acid (AA) as a reducing agent. The synthesized Pd nanoparticles, which are small in size, are evenly dispersed on the surface of the CoFe₂O₄ nanotubes. The hollow structure of the CoFe₂O₄ nanotubes and the uniform distribution of the Pd nanoparticles enhance peroxidase-like activity toward the catalytic oxidation of the peroxidase substrate 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of H₂O₂. The peroxidase-like property of the Pd/CoFe₂O₄ composite nanotubes provides a facile approach for the colorimetric detection of H₂O₂ with a low detection limit. This work provides great potential for Pd/CoFe₂O₄ nanotubes as enzyme-like nanocatalysts to sensitively detect H₂O₂ in biological systems.