Preparation And Application Of Nano-composite Modified Electrode

Nanomaterials have large surface area, high catalytic activity and strong affinity. It has a broad application prospects in the field of electro-catalytic and sensor materials. Studies have shown that the electrochemical process is closely related to the surface properties of the electrode material. Due to the size effect and dielectric confinement effects of nanomaterials, then modification of nanomaterials on the electrode surface can increase the current response, lower limit of detection, greatly improving the detection sensitivity. This thesis is dedicated to the preparation of nanomaterials modified electrode and its electrocatalytic performance, the modified electrode process is simple and convenient, achieved organic combination of nanomaterials, modified electrode and the electroanalytical chemistry.This paper studied the synthesis and catalytic activity of two kinds of nanomaterials. In the first place, this paper studied the electrocatalytic performance of the precious metal nanomaterials. It divided into two parts research. First, using the impregnation-reduction synthesis to get the nano-PtRu alloy, and studied its catalytic oxidation of ascorbic acid from the impact of the scan rate, concentration, PH value and selectivity. The results show that the catalytic reaction process is by diffusion process control, and lower detection limits and good selectivity can be directly used for the detection of ascorbic acid in real life. Second, studied nano-PtRu alloy catalytic oxidation of methanol. Studies have shown that nano-PtRu alloy has excellent catalytic activity for methanol. The paper studied catalytic oxidation of methanol from five different aspects, they are the PH environment, carrier, heat treatment temperature, the reaction temperature and alloy atoms. The results show that, in acidic medium, the porous carbon nanotubes as a carrier, the synthesis of heat treatment temperature is150℃,the reaction temperature reached50℃, the PtRu atomic ratio of3:1, the catalytic activity for methanol is the best. In the next place,Synthesized by a mild wet-chemical synthesis of Fe2O3hollow polyhedron.The tetrakaidecahedral crystals have a threefold axis bound by two top surfaces and twelve side trapezoids surface. Dispensing method will be made of the suspension on modified glassy carbon electrode surface, and in contrast to experiment with the bulk Fe2O3and non-hollow Fe2O3, their catalytic oxidation of nitrite results show that Fe2O3hollow polyhedron catalyze nitrite with high electrocatalytic activity, good stability, sensitivity. It is an ideal material for the production of nitrite sensor.