Pseudo spin-ladder CaCu2O3 nanostructures as potential electrode material for asymmetric supercapacitors

Abstract

Supercapacitors have attracted noteworthy attention due to their high power density and excellent cyclic stability than batteries, despite the limited energy density of the supercapacitors which discourages their practical application. Herein, we have demonstrated the application of a pseudo spin-ladder CaCu2O3 (2-leg) nanostructures as an efficient electrode for the fabrication of a high-performance asymmetric supercapacitor (ASC). CaCu2O3 has received a lot of attention due to its unique magnetic properties and its close relation to high temperature superconductors. The number of Cu-O chains (legs) found in the spin ladder structure of this compound is responsible for its low dimensional magnetism with the Neel temperature of ∼25 K. Electrochemical analysis has revealed that the specific capacitance (specific capacity) of CaCu2O3 based supercapacitor is 205.45 F g−1 (92.45 C g-1) at a current density of 1.5 A g−1 and furthermore CaCu2O3 nanostructures exhibited excellent cyclic stability with capacitance retention of 104% after 10000 continuous cycles. The assembled ASC device (CaCu2O3//AC (activated carbon)) delivered the energy density of 11.8 Wh kg-1 at the power density of 362.5 W kg-1. Evidently, the energy density of 2.21 Wh kg-1 is still retained even at a high power density of 3625 W kg-1. The obtained results demonstrated that the spin-ladder CaCu2O3 electrode materials are potential candidates for high-energy storage applications.