Cobalt hexacyanoferrate as cathode material for na+ secondary battery

Abstract

We investigated structural and electrochemical properties of thin film electrodes of cobalt hexacyanoferrate, NaxCo[Fe(CN)6] 0.90 2.9H2O, against x. The compound exhibits a high capacity of 135 mAh/g and an average operating voltage of 3.6V against Na, with a good cyclability. The discharge curve exhibits two plateaus at ≈3.8 and ≈3.4 V, which are ascribed to the reduction processes of Fe3+ and Co3+, respectively. The ex situ X-ray diffraction (XRD) profiles reveal the robust nature of the host framework against Na+ intercalation/deintercalation. Thus, cobalt hexacyanoferrate is a promising candidate for the cathode material of sodium-ion secondary battery (SIB). Copyright © 2013 The Japan Society of Applied Physics.