Arginine-assisted Thermal Decomposition for Synthesis of Nanosized Co3O4 with Enhanced Capacitance

Arginine-assisted thermal decomposition technique was used to prepare nanosized Co3O4 (A-Co3O4) with its supercapacitive performances checked. A-Co3O4 was characterized by different techniques such as X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and scanning electron microscopy. Brunauer-Emmett-Teller analysis revealed that A-Co3O4 had a larger specific surface area than Co3O4 prepared by conventional calcination without arginine (F-Co3O4). Electrochemical performances of A-Co3O4 based electrode were better than that of the F-Co3O4 based electrode. Cyclic voltammetric results showed the specific capacitances of A-Co304 and F-Co3O4 were found to be 259.2 and 122.2 F/g at a scan rate of 0.01 V/s. Long-term galvanostatic charge-discharge cycling tests indicated the specific capacitance for A-Co3O4 and F-Co3O4 were 128.6 F/g and 106.4 F/g with 104.7% and 103.3% capacitance retention after 1000 cycles at a current density of 5.0 A/g. Electrochemical impedance spectra analysis showed the charge transfer resistance (Rct) of A-Co3O4 was 7.56 Omega and that of F-Co3O4 was 15.56 Omega. All the results indicated the A-Co3O4 exhibited superiority originated from large surface area with porous structure.