Development of CoTe2, CoS2, and CoSe2 Electrode Material for the Asymmetric Supercapacitors

Abstract

Supercapacitors play a crucial role in electrical energy storage and conversion applications today due to their high power density and ability to integrate with various energy conversion devices. Many efforts have been made to address issues such as low energy density and finding efficient electrode materials to achieve high capacitances. Layered transition metal dichalcogenides have shown great potential in energy storage applications because of their numerous active edges, diverse electrochemical kinetics, and unique sandwich structure. Therefore, researchers have been exploring a meticulous method to formulate multiscale CoS2, CoSe2, and CoTe2 nanoarchitectures to enhance the storage characteristics of supercapacitors. This study employed a single-step facile chemical reaction method to form CoSe2, CoTe2, and CoS2 nanostructures. The synthesized CoTe2 material demonstrated a specific capacity of 370 C g-1 at 1 A g-1 alongside reliable cycling robustness over 10,000 cycles (98%), superior to CoSe2 and CoS2 electrodes. An alkaline hybrid asymmetric supercapacitor based on CoTe2 achieved a 157 F g-1 specific capacitance with 56 Wh kg-1 specific energy and a long cycling life of 97% capacitance retaining over 10,000 cycles. These findings reveal the significant potential of cobalt chalcogenide nanostructures to be applied as prototype electrodes for supercapacitor devices.