Nanostructured Fe-Substituted LaMnO₃ Perovskites as a High-Performance Electrode for Supercapacitors

Abstract

With the rise in eco-friendly energy needs, supercapacitors have become an essential option for energy storage devices. For this purpose, new and efficient electrode materials are required for use in supercapacitors with higher durability and longer storage lifespan. For this, transition metal oxides are preferred, owing to their high capacitance values, for energy storage in supercapacitors. In this context, LaMn1-xFexO3 (x = 0.0, 0.33, 0.66, and 1.0) are presented here with a better electrochemical response, prepared following sol−gel auto-combustion route to optimize the influence of Fe substitution at Mn-site in LaMnO3. X-ray diffraction technique confirms the formation of the orthorhombic phase for both LaFeO3 and LaMnO3. Cyclic voltammetry was performed at a constant potential window of −0.2 to 0.4 V and varying scan intervals (0.01−0.2 Vs−1). The oxidation/reduction peak occurrences revealed the pseudocapacitive behavior and the apparent Nyquist plot showed less charge transfer resistance. Thus, marvelous results expose the synthesized composition LaMn1-xFexO3 at x = 0.0, 0.33, 0.66, and 1.0, a promising material for the electrodes.