Electrochemical Behaviour of Lithium, Sodium and Potassium Ion Electrolytes in a Na 0.33 V 2 O 5 Symmetric Pseudocapacitor with High Performance and High Cyclic Stability

A high‐performance symmetric supercapacitor was fabricated using a Na 0.33 V 2 O 5 nanocomposite synthesized by means of a simple co‐precipitation technique. The structural and morphological investigation showed that the synthesized Na 0.33 V 2 O 5 nanocomposite exhibited a monoclinic structure with a nanorod‐like morphology. The electrochemical properties of the Na 0.33 V 2 O 5 symmetric supercapacitor were studied utilizing three different aqueous electrolytes, such as 1 M of LiCl , NaCl and KCl, respectively. Interestingly, the fabricated Na 0.33 V 2 O 5 symmetric supercapacitors exhibited excellent electrochemical capacitance behaviour in all the electrolytes with a maximum specific capacitance value of 168 F g −1 in 1 M LiCl, 146 F g −1 in 1 M NaCl and 132 F g −1 in 1 M KCl electrolytes at 0.5 A g −1 discharge current density. In addition, Na 0.33 V 2 O 5 symmetric supercapacitors demonstrated an excellent cyclic stability in 1 M NaCl electrolyte with high capacitance retention of approximately 81 % after 50 000 charge/discharge cycles.