TITLE:
Capacitive Properties of Mesoporous Mn-Co Oxide Derived from a Mixed Oxalate
AUTHORS:
Yong Yan, Bingcai Wu, Cuihong Zheng, Daolai Fang
KEYWORDS:
Supercapacitors; Manganese Oxide; Solid-State Reaction; Cyclic Voltammetry; Capacitive Performance
JOURNAL NAME:
Materials Sciences and Applications,
Vol.3 No.6,
June
19,
2012
ABSTRACT: A mesoporous Mn-Co oxide for supercapacitors was derived from a mixed oxalate Mn0.8Co0.2C2O4·nH2O, which was synthesized by a solid-state coordination reaction at room temperature. The synthesized mixed Mn-Co oxalate was decomposed in air at 250°C, resulting in a tetragonal spinel Mn-Co oxide with a primary particle size less than 100 nm. The obtained Mn-Co oxide presents a mesoporous texture with a specific surface area of 120 m2·g﹣1. Electrochemical properties of the Mn-Co oxide electrode were investigated by cyclic voltammetry and galvanostatic charge/discharge in 6 mol·L﹣1 KOH electrolyte. The Mn-Co oxide electrode delivered specific capacitances of 383 and 225 F·g﹣1 at scan rates of 2 and 50 mV·s﹣1, respectively. Subjected to 500 cycles at a current density of 1.34 A·g﹣1, the symmetrical Mn-Co oxide capacitor showed specific capacitance of 179 F·g﹣1, still retaining ~85% of its initial capacitance. The obtained Mn-Co oxide material showed good capacitive performance, which was promising for supercapacitor applications.