Nano SnO_2-Al_2O_3 mixed oxide and SnO_2-Al_2O_3-carbon composite oxides as new and novel electrodes for supercapacitor applications

摘要

New nano-materials like SnO_2-Al_2O_3 and SnO_2-Al_2O_3-carbon were synthesized by a single step hydrothermal method in searching for novel mixed oxides with high electrochemical double layer capacitance. A SnO_2-Al_2O_3-carbon sample was calcined at 600 deg C and tested for its performance. The source of carbon was tetrapropyl ammonium hydroxide. The capacitive behavior of SnO_2 was compared to the performance of SnO_2-Al_2O_3, SnO_2-Al_2O_3-carbon and calcined SnO_2-Al_2O_3-cai-bon using the techniques of cyclic voltammetry, double potential step, chronopo-tentiometry and E-log I polarization. In 0.1M NaCl solutions, SnO_2-Al_2O_3 gave the best performance with a value of 119 F g~(-1) and cycled 1000 times. The nano-material mixed oxides were characterized by TEM, XRD, ICP-AES and SEM-EDAX.