LAUSR

Abstract The present study demonstrate the development of novel aqueous asymmetric supercapacitor based on polygonal integrated oxide layer ((Fe,Cr) 2 O 3 ) as the anode and spherical MnO 2 nanoparticles as the cathode. The polygonal (Fe,Cr) 2 O 3 integrated oxide layer was obtained by the simple thermal oxidation method and low-cost, scalable chemical route was employed for the synthesis of spherical MnO 2 nanoparticles. Furthermore, electrochemical investigations of asymmetric supercapacitor (ASC) studied in aqueous electrolytes show an extended operating voltage of 1.6 and 2.0 V with the maximum specific capacitance of 34 and 37 Fg -1 in KOH and Na 2 SO 4 , respectively. The observed energy density and power density of ASC in Na 2 SO 4 (or KOH) electrolyte is 20.89 (or 12.36) Whkg −1 and 2173.913 (or 1739) Wkg −1 , respectively. ASC shows the better capacitance retention over the 5000 cycles in both the electrolytes. Therefore, present study open-up new construction of inexpensive petty (Fe,Cr) 2 O 3 anode material for the development of high energy density ASCs.