Microwave-assisted synthesis of CuxTey as an anode material for supercapacitors

The low negative-electrode capacitance of supercapacitors results in low energy density, thereby severely limiting their practical applications. In this study, CuxTey composite anode materials were prepared using a microwave-assisted method and subsequently characterized using various techniques. The three-electrode performance of the material was tested using a 6 M KOH alkaline solution, and results showed that the multiple valence states of Cu element provided abundant redox active sites. These sites conferred the CuxTey electrode with excellent capacitance (708 mAh g(-1)). Thus, symmetric supercapacitor devices were constructed with a power of 3056 Wh kg(-1) and an energy density of 73 Wh kg(-1) in a relatively superior position. The capacitance retention for 1000 consecutive charge-discharge cycles was 71.3%, and the Coulomb efficiency was 99.1%.