Facile preparation of MnO-TiO nanotube arrays composite electrode for electrochemical detection of hydrogen peroxide.

The MnO-TNTA composite electrodes were obtained through depositing MnO into TiO nanotube arrays (TNTA) by successive ionic layer adsorption reaction (SILAR) and subsequent hydrothermal method. The MnO-TNTA nanocomposites were used as electrochemical sensors for the detection of hydrogen peroxide (HO). The preparation conditions of MnO-TNTA electrodes and test conditions affect the electrochemical detection performance significantly. The optimal conditions are listed as follows: the number of SILAR cycles, 6 times; KMnO solution temperature, 50 °C; supporting electrolyte, 0.5 M NaOH. Under these conditions, the MnO-TNTA electrode exhibits the best performance for detecting HO. The optimized MnO-TNTA electrode has a minimum detection limit of 0.6 μM (S/N = 3) and a linear range of 5 μM ∼ 13 mM, which is much superior to the previously-reported electrodes. Moreover, the optimized MnO-TNTA electrode possesses high selectivity, excellent stability and good reproducibility in the detection of HO. When used in the determination of HO content in actual samples including disinfectant and milk, it also shows good accuracy, ideal recovery (96.00% ∼ 102.67%) and high precision (RSD < 4.0%).