将多壁碳纳米管(MWCNT′s) 1 mg分散在5 g·L-1壳聚糖溶液中,并滴涂在玻碳电极表面,将上述电极置于氯铂酸(1+99)溶液中,于电位-0.2 V下电沉积90 s,制得纳米铂-多壁碳纳米管-壳聚糖修饰玻碳电极(nano Pt/MWCNT′s-CTS/GCE)。采用扫描电子显微镜对该电极表面结构进行了表征,并用循环伏安法和计时电流法对该电极的电化学性能进行了研究。试验表明:在pH 7.0的0.1 mol·L-1磷酸盐底液中,该传感器对过氧化氢具有明显的电催化还原作用。过氧化氢浓度在6.30×10-7~1.52×10-3mol·L-1范围内与还原峰电流呈线性关系,检出限(3S/N)为2.13×10-7mol·L-1。对0.35 mmol·L-1过氧化氢标准溶液连续测定8次,测定值的相对标准偏差(n=8)为0.27%。

One mg of multi-wall carbon nano-tubes (MWCNT′s) was dispersed in 5 g·L-1 chitosan solution, and the dispersion was dropped on the surface of glassy carbon electrode (GCE), which was then electrodeposited in H2［PtCl6］ (1+99) solution at -0.2 V for 90 s to have it filmed with platinum nanoparticles on its surface. The modified electrode thus prepared was named abbreviately as nano Pt/MWCNT′s-CTS/GCE. The microstructure of the surface of the modified electrode was characterized by SEM and its electrochemical property was studied by cyclic voltammetry and chronoamperometry. It was found that the modified electrode exhibited excellent electrocatalytic responses towards the reduction of H2O2. Linear relationship between values of reduction peak current and concentration of H2O2 was obtained in the range from 6.30×10-7 to 1.52×10-3mol·L-1, with detection limit (3S/N) of 2.13×10-7mol·L-1. Precision of the method was tested at the concentration level of 0.35 mmol·L-1 H2O2 standard solution for 8 determinations giving value of RSD (n=8) of 0.27%.