One-step fabrication of chitosan-hematite nanotubes composite film and its biosensing for hydrogen peroxide

This work reports on a novel chitosan-hematite nanotubes composite film on a gold foil by a simple one-step electrodeposition method. The hybrid chitosan-hematite nanotubes (Chi-HeNTs) film exhibits strong electrocatalytic reduction activity for H2O2. Interestingly, two electrocatalytic reduction peaks are observed at -0.24 and -0.56 V (vs SCE), respectively, one controlled by surface wave and the other controlled by diffusion process. The Chi-HeNTs/Au electrode shows a linear response to H2O2 concentration ranging from 1 x 10(-6) to 1.6 x 10(-5) mol L-1 with a detection limit of 5 x 10(-8) mol L-1 and a sensitivity as high as 1859 mu A mu M-1 cm(-2). (C) 2007 Elsevier B.V. All rights reserved.