Hybrid Bi2Te3/Bi2TeO5 nanoscale flakes via chemical disproportionation under microwave: Electrochemical supercapacitor applications

In this study, bismuth telluride–based hybrids consisting of nanosheets were successfully prepared by disproportionation induced by microwave irradiation and applied on supercapacitor electrodes. Various analytical techniques were adopted to analyze the structure and composition of Bi 2 Te 3 /Bi 2 TeO 5 . The unique disproportionation (Te 0 →Te 2+ +Te 4+ ) results in an interlocking nanosheet, in which the lamellar interspersed structure on the lamella can be visualized through high-magnification scanning electron microscopy. The large layer spacing with the interspersed structure provides more storage sites for electrolyte ion interactions and allows for better stabilization of the electrode structure. Result of electrochemical studies indicates that Bi 2 Te 3 /Bi 2 TeO 5 enables a capacity of 860 F g −1 (1 A g −1 ) and maintains 74.5% of the initial capacity through 2000 charge/discharge cycles. The Bi 2 Te 3 /Bi 2 TeO 5 anode is integrated into an ultracapacitor to attain a remarkable energy density of 89 Wh kg −1 in 6 M KOH.