Binderless fabrication of amorphous RuO2 electrode for electrochemical capacitor using spark plasma sintering technique

The spark plasma sintering (SPS) technique was successfully used to mold a hydrous amorphous RuO2electrode without any additives and binders. At the cyclic voltammetry (CV) scan rate of 1 mV s−1, the electrochemical capacitances of the RuO2 electrodes are 600–700 F g−1 for the entire electrode. An increase in the SPS current during the compaction led to the crystallization and dehydration of RuO2, which in turn, resulted in a significant decrease in its capacitance. There is room to improve the rate properties as we observed a steep drop in the capacitance when the CV scan rate was raised.