TiO2纳米颗粒电化学后处理对超级电容器性能的改善

通过水热法以硫酸钛为钛源制备TiO2 纳米颗粒，然后将样品制成电极模拟超级电容器.1)通过SEM观察TiO2 纳米颗粒的微观形貌，其直径大小分布在30～50 nm， 并通过XRD测定TiO2 纳米颗粒的晶相结构为锐钛矿型；2)对超级电容器进行电循环处理，其比电容从10 mF/cm2增长到103 mF/cm2，并达到稳定，说明电循环处理大幅度提高了该样品的电导率；3)CV曲线中观察到一对明显的氧化还原峰，其比电容主要起源于该氧化还原反应. 恒流充放电和CV曲线计算所得比电容基本一致，阻抗谱图谱也清晰地显示了氧化还原反应所对应的极化电阻的存在.

The enhanced performance of TiO2 nanoparticle supercapacitor via electrochemical post-processing

In this paper work， TiO2 nanoparticles were prepared by hydrothermal method using titanium sulfate as titanium source， and then the samples were made into electrode simulation supercapacitors. 1) The microstructure of TiO2 nanoparticles was observed by SEM， and the diameter of TiO2 nanoparticles was 30～50 nm. The crystal structure of TiO2 nanoparticles was anatase confirmed by XRD； 2) the supercapacitor is subjected to an electrical cycle process with an increase of specific capacitance from 10 mF / cm2 to a stable value of 103 mF/cm2， which suggests that the conductivity of the sample was significantly improved by the electric cycle treatment； 3) a pair of obvious redox peaks was observed in the CV curve， and the specific capacitance of supercapacitor mainly originate from the corresponding redox reaction. The specific capacitance values are in agreement with each other， calculated by CV curve and the constant current charge/discharge curve， respectively. In addition， the polarization resistance due to Redox reaction was demonstrated by the measured impedance spectra for the fabricated nanoparticle supercapacitor.