首先以Co(NO3)2·6H2O和C4H6N2为原料合成基于Co的金属有机框架结构(Co-MOF),在空气中煅烧后获得片状Co3O4多孔材料。该材料所具有的有序孔道结构不仅提供了大量的电催化活性位点,并且有助于电解液、待测物和中间产物的扩散和吸脱附,改善了电催化动力学,获得了较高的电催化活性。作为葡萄糖的检测电极,Co3O4修饰的玻碳电极(Co3O4/GCE)在2.3μmol/L到1.0mmol/L线性范围内灵敏度为617.4μA/(mmol·cm2),检测限为0.23μmol/L,响应时间为5.9s。同时,Co3O4/GCE对葡萄糖检测表现出优异的选择性、可靠的重复性和稳定性,证明该Co3O4材料在葡萄糖电化学传感器领域具有实际应用的价值。
Co(NO3)2·6H2O and C4H6N2 were used as raw materials to synthesize Co-MOF precursor.After calcination in air,porous Co3O4 flakes were obtained.The ordered pores not only provide amounts of electrocatalytic activity sites,but also contributed to the diffusion and desorption of electrolyte,glucose and intermediate products,leading to improved electrocatalytic activity.As a glucose detection electrode,Co3O4 modified glassy carbon electrode (Co3O4/GCE) displayed a sensitivity of 617.4μA/(mmol·cm2),detection limit of 0.23μmol/L and response time of 5.9s in the linear range of 0.23μmol/L to 1.0mmol/L.Moreover,Co3O4/GCE shown excellent selectivity,reliable repeatability and stability for glucose detection,demonstrating that the porous Co3O4 flakes had practical application in the field of glucose electrochemical sensor.
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