Modulating structure and electrochemical performance of LaMnO3–NiO composites through auto-combustion

LaMnO 3 –NiO (LM-NiO) composites were synthesized via a facile auto-combustion method to optimize the synergistic interaction between perovskite and transition metal oxide phases for high-performance supercapacitor electrodes. Systematic variation of the LaMnO 3 :NiO weight ratio revealed that the 7:3 composition exhibits a mesoporous architecture with the highest specific surface area (22 m 2 g −1 ) and well-balanced mixed-valence states of Mn (Mn 2+ /Mn 3+ /Mn 4+ ) and Ni (Ni 2+ /Ni 3+ ). These structural and electronic features enable superior redox activity, delivering a high specific capacitance of 689 F/g at 10 mV s −1 and 694 F g −1 at 1 A g −1 , along with excellent cycling stability (86% capacitance retention after 5000 cycles). Enhanced performance of the composite arises from improved ion-diffusion pathways, increased active sites, and reduced charge-transfer resistance, enabled by interfacial coupling between LaMnO 3 and NiO. This work demonstrates an effective strategy for tailoring perovskite–oxide composites to achieve high-energy-density, long-cycle-life supercapacitor electrodes.