Facile chemical synthesis of cobalt tungstates nanoparticles as high performance supercapacitor

• Published in: Journal of materials science. Materials in electronics Vol. 27; no. 5; pp. 4541 - 4550
• Main Authors: Adib, Kourosh, Rahimi-Nasrabadi, Mehdi, Rezvani, Zolfaghar, Pourmortazavi, Seied Mahdi, Ahmadi, Farhad, Naderi, Hamid Reza, Ganjali, Mohammad Reza
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.05.2016; Springer Nature B.V
• Subjects: Capacitance; Characterization and Evaluation of Materials; Chemistry and Materials Science; Cobalt; Electrodes; Materials Science; Nanoparticles; Optical and Electronic Materials; Optimization; Spectroscopy; Synthesis (chemistry); Tungstates; Supercapacitive Performance; Electrochemical Impedance Spectroscopy; CoWO4; Tungstate Solution; Electroactive Material
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-016-4329-4

Cobalt tungstate (CoWO 4 ) nanoparticles were synthesized by a chemical precipitation reaction in aqueous ambient involving direct addition of cobalt ion solution to the solution of tungstate reagent. Optimization of the synthesis procedure was carried out using Taguchi robust design as statistical method. In order to controllable, simple and fast synthesis of CoWO 4 nanoparticles, effects of some synthesis conditions such as reagents concentrations (i.e., cobalt and tungstate ions), flow rate of cobalt feeding and temperature of the reactor on the particle size of synthesized CoWO 4 were investigated by the aid of an orthogonal array (OA 9 ). The results of optimization process showed that CoWO 4 nanoparticles could be prepared by controlling the effective parameters and at optimum conditions of synthesis procedure, the size of prepared CoWO 4 particles was about 55 nm. Chemical composition and microstructure of the prepared CoWO 4 nanoparticles were characterized by means of XRD, SEM, TEM, FT-IR spectroscopy, UV–Vis spectroscopy and fluorescence. The supercapacitive behavior of the CoWO 4 electrode has been investigated by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. The CoWO 4 electrode indicates high specific capacitance of 378 F g −1 at scan rate of 2 mV s −1 in 2.0 M H 2 SO 4 electrolyte. Therefore, the prepared electrode could be potential electrode materials for supercapacitors. Moreover, an excellent rate performance, good capacitance retention (~95.5 %) was also observed during the continuous 4000 cycles.