Flake-like Cu2O on TiO2 nanotubes array as an efficient nonenzymatic H2O2 biosensor

This work provides a new method for fabrication of the flake-like Cu2O/TiO2 nanotubes array (TNA) electrode as a H2O2 sensor. The flake-like Cu2O/TNA electrode was successfully constructed by potentiostatic electrodeposition combining subsequent cyclic voltammetry (CV) technology in NaOH solution. The catalytic performance of the sensor was studied in 0.1 M phosphate buffer (PBS, pH = 7.4). It was found that the flake-like Cu2O/TNA electrode displayed a good catalytic performance towards the reduction of H2O2 with a response time of 4 s, a wide linear dependence on a concentration of H2O2 from 0.5 mM to 8 mM, a good sensitivity of 412.11 mu A cm(-2) mM(-1) and a detection limit of 90.5 mu M at a working voltage -0.40 V (vs. Hg/Hg2Cl2). The electrocatalytic mechanism of the flake-like Cu2O/TNA electrodes was also proposed. (C) 2016 Elsevier B.V. All rights reserved.