CeO2 mixed LaMnO3 nanocomposites were synthesized using a hydrothermal route. Sodium dodecyl sulfate was used as the surfactant. Cerium oxide was mixed in the LaMnO3 perovskite nanoparticles and the crystal structure was confirmed by X-ray diffraction and X-ray photoelectron spectroscopy. Field emission scanning electron microscopy and high-resolution transmission electron were used to identify the morphology of the prepared nanoparticles. The CeO2 mixedLaMnO(3) nanocomposites exhibited a mesopore size and high surface area in the N-2 adsorption/desorption measurements. Three electrode measurements indicate the CeO2 mixed LaMnO3 nanocomposites to be a suitable negative electrode material for supercapacitor device fabrication and exhibited a high specific capacitance of 262 F g(-1) at a specific current of 1 A g(-1). The asymmetric supercapacitor device showed a maximum energy density of 17.2 W h kg(-1) at a power density of 1015 w kg(-1). These electrochemical studies show that CeO2 mixed LaMnO3 nanocomposites are an appropriate negative electrode material for supercapacitor device fabrication. (C) 2017 Elsevier B.V. All rights reserved.