Electrodeposition of Ti0_2 Nanoparticles on Multiwalled Carbon Nanotube Arrays for Hydrogen Peroxide Sensing

摘要

In this work, an amperometric H_20_2 sensor based on TiO_2/MWCNTs electrode is reported. Ti0_2 nanoparticles were synthesized on vertically aligned multiwalled carbon nanotube (MWCNT) arrays by electrodeposition. The morphology of the TiO_2/MWCNTs was characterized by scanning electron microscopy (SEM). The electrochemical performance of the TiO_2/MWCNTs electrode for detection of H_2O_2 was investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry. The TiO_2/MWCNTs electrode displays high electrocatalytic activity towards oxidation of H_20_2 in 0.1 M phosphate buffer solution (PBS, pH 7.4). At an applied potential of +0.40 V, the TiO_2/MWCNTs electrode exhibits a linear dependence (R=0.998) in the H_20_2 concentration up to 15.0 × 10~(-3) M with a sensitivity of 13.4 μA mM~(-1) and detection limit of 4.0 × 10~(-7) M with signaloise = 3. The optimal response time is less than 5 s with addition of 1 mM H_2O_2. The Ti0_2/MWCNTs electrode presents stable, high sensitivity and also exhibits fast amperometric response to the detection of H_2O_2, which is promising for the development of H_20_2 sensor.