Hydrothermal Synthcsis Of Micro/Nano Structures And Their Electrochemical Properties

In the 21st century, with the development of nanotechnology, studies on nanomaterials have been getting deeper and more mature. Researchers do not only pay attention to simply synthesize nanomaterials or explore their morphology and performance, but pay more attention to synthesize nanomaterials with special performance. Nanomaterials have some special properties different from the massive materials due to the surface effect, small size effect and macroscopic quantum tunneling effect. For example, nanomaterials can be applied in biological sensors, industrial catalysis, energy storage, information transmission and so on.In this thesis, some micro/nano structures of metal oxides were prepared by the hydrothermal method. We also researched the effect of experimental conditions and parameters in order to find the optimum experiment conditions. And, the corresponding electrochemical performances were also analyzed according their structure and characteristics. The research results are displayed as follows:1. Preparation of six petals of ZnO-CuO composite microstructuresFirstly, pure CuO and ZnO microstructures were prepared by using hydrothermal method. On this basis, through controlling the proportion of copper acetate and zinc acetate, six petals shape ZnO-CuO composite microstructures with six petals shape were synthesized. The crystal structure, morphology and phase composition were characterized utilizing the means such as SEM, XRD and TEM. The morphology observations and structure analysis of ZnO-CuO composite microstructures and the related byproducts revealed that there was a morphology evolution.2. Non-enzymatic ascorbic acid biosensor based on Cu/CuO micro/nano materialsCu/CuO micro-nano materials were synthesized by hydrothermal reaction on the nickel foam. The crystal structure, morphology, phase composition were characterized utilizing the means such as SEM, XRD. Then AA sensor was tested with the electrode that maked by the material directly. The cyclic voltammetry and chronoamperometry test results display that the Cu/CuO micro-nano material sensor has a higher current response and good sensitivity. In addition, the electrode material has such characters: the simple preparation method, super function and low cost.3. Non-enzymatic ascorbic acid sensor based on Fe2O3 nanostructuresFe2O3 nanostructures that like red blood cell were synthesized by hydrothermal reaction. The crystal structure, morphology, phase composition were characterized. The as-prepared Fe2O3 nanomaterials were modified on the carbon paste electrode. Non enzymatic AA sensor then was constructed based on Fe2O3 nanomaterial. The electrochemical properties of sensor were tested in alkaline electrolyte. The results show that the sensor has good performance. Compared with the sensor that based on gold electrode and glassy carbon electrode, this sensor has many advantages:low cost, using simply, expediently and repeatedly.4. Growth of cobalt hydroxide on carbon cloth and its supercapacitors propertiesCobalt hydroxide nanoflakes were synthesized on soft carbon cloth by hydrothermal reaction. The morphology was characterized by SEM. The nanoflakes were further applied as binder-free electrodes for supercapacitors and the properties were researched simply, combined with the material’s nature and feature. The cyclic voltammetry and chronoamperometry test results display that Co(OH)2 nanoflakes have a high specific capacitance, remarkable rate capability and good capacity retention.