Sol-Gel-Derived RuOx Nanoparticles for Supercapacitors

• Main Authors: Wei-Chun Chen, 陳瑋駿
• Other Authors: 胡啟章
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/55052579974210592676

碩士 === 國立中正大學 === 化學工程研究所 === 91 === The capacitive performance of composites composed of activated carbon powers and hydrous ruthenium oxide nanoparticles is demonstrated in this work. Due to the high cost of ruthenium precursors, the C-RuOx composite is a promised electrode material for practical usage. The electrochemical characteristics of composite electrodes composed of AC powders and the hydrous RuOx nanoparticles prepared by a modified sol-gel method are investigated for the application of supercapacitors. The capacitive performance of RuOx nanoparticles prepared by a modified sol-gel method was analyzed by electrochemical measurements in the first part. The hydrous RuOx is an ideal material for the application of supercapacitors. The specific capacitance is still high by mixing 90 wt.% AC significantly reducing the cost. The conductivity of SS mesh can be improved as well as graphite by coating gold and ruthenium onto the surface. The composite coated on the pretreated SS mesh is more applicable in industry than that on the graphite. The electron hoping became facile with lowering the nanoparticles size of RuOx and controlling the size distribution. The maximal specific capacitance of RuOx is 1580 F/g. The resistance of solid-solid interfaces was increased by further lowering the size of nanoparticles. The ability of electron hoping and the specific capacitance was lowered with this further decrease in size of RuOx at the same time. On the basis of the equivalent circuit diagram the solid-solid and the composite-electrolyte interfaces, contributed their impedance in the relatively high and low frequency regions. The ability of electron hoping that has been proved by EIS responses is the key factor determining the capacitive performance of AC-RuOx. By textural analyzing, the RuOx nanoparticles have successfully composite prepared by the modified sol-gel method. The RuOx does not crystallize whether it has been annealed in air or not. There may be RuO2 and RuO3 in the RuOx nanoparticles by XPS analyzing. In the quantum effect, the location of maximum absorbance peak of RuOx nanoparticles has red-shift in UV spectra by increasing the particles size.