Highly dispersed silver imbedded into TiN submicrospheres for electrochemical detecting of hydrogen peroxide

We report the fabrication of silver nanoparticles evenly imbedded into TiN submicrospheres via one-pot solvothermal reaction and subsequent nitridation for electrochemical detecting of hydrogen peroxide. The precursor of TiO₂ submicrospheres and high dispersion of silver nanoparticles are regulated by the alcoholysis of tetrabutyl titanate and reducibility of enol in vitamin C. The ion nitriding promoted the conductivity and micro-nano porous structure on the surface of TiN submicrospheres, which increase the dispersity of silver nanoparticles and make contributions to avoid aggregations. More importantly, the electrochemical response of Ag-TiN submicrospheres to H₂O₂ was remarkably enhanced due to the co-effects of Ag and N-doping. It provides a superior sensing performance for electrochemical detection of hydrogen peroxide at - 0.3 V with a high sensitivity of 33.25 μA mmol L^-1 cm^-2, wide linear range of 0.05-2100 μM and low detection limit of 7.7 nM. The fabricated sensor also reliably applied in detection of H₂O₂ in milk samples with good reproducibility, repeatability and storage stability.