Mo-doped La2Ce2CO7 with varied concentrations are prepared by the traditional citrate-nitrate combustion method. The effects of the phase structure of Mo-doped La2Ce2O7 are investigated by X-ray diffraction, scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and conductivity measurements. X-ray diffraction patterns reveal that all La2-xMoxCe2O7+delta samples have a cubic structure. Neverly, hole can be found on the surface of the samples from scanning electron microscopy. Raman spectra show that the different vibrating structures of pellets can be changed by introducing Mo into La2Ce2O7. Detailed X-ray photoelectron spectroscopy studies on the oxidation states of La2Ce2O7 and La1.85Mo0.15Ce2O7+delta indicate ratios of O-c to O-T (O-T = O-c + O-L) are between 32.21% and 46.24%. The conduction behaviour of Mo doped La2Ce2O7 electrolyte is seriously researched under air and 5%H-2-95%Ar conditions at 350-700 degrees C,and the highest conductivity of 7.36 X 10(-3) and 1.65 X 10(-2) Scm(-1), respectively, are obtained with La1.85Mo0.15Ce2O7+delta pellets at 700 degrees C. The highest power density of single cells with the La1.85Mo0.15Ce2O7+delta electrolyte is approximately 0.643 Wcm(-2) at 700 degrees C, suggesting that Mo-doped La2Ce2O7 can be used to substantially improve the electrochemical performance of low-temperature solid oxide fuel cells. (C) 2018 Elsevier Ltd. All rights reserved.