Abstract

In this study, a nanostructured screen-printed carbon electrode (nanoSPCE) was modified with silica-based composite films containing metal oxides (MnO₂ or CuO) without and with graphene oxide (GO). According to scanning electron microscopy results, uniform thin films with encapsulated metal oxides and GO were formed on the surface of nanoSPCEs. The electrochemical parameters of the modified electrodes were measured by cyclic voltammetry for the non-enzymatic determination of H₂O₂. Because of the combined action of GO and metal oxides, the modified electrodes have improved electrocatalytic performance for the determination of H₂O₂ in phosphate buffer solutions. NanoSPCE/MnO₂/GO/SiO₂ and nanoSPCE/CuO/GO/SiO₂ exhibited stable current-voltage responses and good sensing for H₂O₂ with a wide linear detection range of 0.005–0.5 mM and 0.05–0.3 mM, respectively.

摘要

在这项研究中，纳米结构的丝网印刷碳电极 (nanoSPCE) 用含有金属氧化物 (MnO ₂或 CuO) 的二氧化硅基复合膜进行了修饰，没有和有氧化石墨烯 (GO)。根据扫描电子显微镜结果，在nanoSPCEs表面形成了包裹有金属氧化物和GO的均匀薄膜。通过循环伏安法测量修饰电极的电化学参数，用于非酶法测定 H ₂ O ₂。由于GO和金属氧化物的共同作用，修饰电极在磷酸盐缓冲溶液中测定H ₂ O _{2 时}具有改进的电催化性能。NanoSPCE/MnO ₂ /GO/SiO₂和nanoSPCE/CuO/GO/SiO ₂表现出稳定的电流-电压响应和对H ₂ O _{2 的}良好传感，线性检测范围分别为0.005-0.5 mM 和0.05-0.3 mM。