Multiwalled Carbon Nanotubes Decorated with Copper(II)/1H-Benzotriazole Complex via π–π Interaction for Enhanced Electroreduction of Hydrogen Peroxide

In this work, multiwalled carbon nanotubes (MWCNT) were facilely functionalized with copper(II)/1Hbenzotriazole (BTA) complex (Cu-BTA) via π–π interaction. Cyclic voltammetry (CV), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterize the Cu-BTA modified MWCNT, denoted as Cu-BTA/MWCNT. Experimental results indicate that Cu-BTA is redox-active and the surface of MWCNT was uniformly covered with the thin film of Cu-BTA. Further investigation shows that Cu-BTA/MWCNT exhibited excellent catalytic capabilities towards the reduction of hydrogen peroxide. The sensors based on Cu-BTA/MWCNT modified glassy carbon electrodes (GCE), denoted as Cu-BTA/MWCNT/GCE, present wide linear range, low detection limit and high sensitivity for the determination of hydrogen peroxide. Using amperometric i–t measurement, the linear range, the limit of detection (LOD) and the sensitivity for the detection of H2O2 are 5 × 10–7∼1.0 × 10–3 M, 2.21 × 10–7 M and 1.33 μA/μM, respectively. Cu-BTA/MWCNT/GCE was also successfully used in the determination of hydrogen peroxide because of its excellent selectivity and stability.