Nanodiamond ceramic composite as a new kind of surface-renewable electrode (NDCE) for electrochemical application

In the present work, we report the fabrication of a new surface-renewable electrode based on a sol–gel derived nanodiamonds ceramic nanocomposite and application of a sensitive nonenzymatic hydrogen peroxide (H2O2). The electrode was fabricated by dispersing nanodiamonds powder into a solution of the sol–gel precursors containing methyl triethoxysilane in methanol and hydrochloric acid. After moulding the sol-gel in cylindrical plastic tube, nanocomposite was dried and then, it can be used as a surface-renewable electrode to which we named as a nanodiamonds ceramic electrode (NDCE). We use the hexacyanoferrate(II/III) model redox system to compare the NDCE with a conventional carbon ceramic electrode and showed a highly improved electron transfer rate at the NDCE. The electrochemical investigations have shown that the resulting NDs ceramic electrode has strong electrocatalytic activity toward H2O2 reduction. In the optimum conditions, the linear response range of the constructed H2O2 sensor was from 0.2 to 180 μM with a detection limit of 0.35 μM (S/N = 3). Advantages such as good mechanical and chemical stability, ease of fabrication, and reproducible preparation make the NDCE a potentially useful and widely applicable renewable electrode for use in routine analysis.