| In this paper, we employ high-temperature organic precursor sintering method to prepare nanoscale MnO/C composite, the performance of which has been studied in further research. Testing methods, such as XRD, TG, SEM, TEM and XPS, were hired to analyze the chemical composition and microstructure; meanwhile, electrochemical properties of the composite are tested via galvanostatic charge-discharge measurement and cyclic voltammetry.MnO/C nano-composite is "core - shell" structured. The composite exhibits a display of granular materials, the size of which ranges between 100200 nm. The first lithiation capacity of the composite is 1189.5 mAh g-1, and the following delithiation capacity is 706.8 mAh g-1, making the columbic efficiency 59.4%. The delithiation capacity of the compostie maintains at 424.66 mAh g-1 after 45 cycles. The amorphous carbon contained in MnO/C composite not only does some good to the conductivity and distribution of MnO, but also relief volume expansion and accelerates the charge transfer rate of electrochemical reaction.This paper studies different factors of composite fabrication, such as: types of precursors, calcination duration, calcination temperature and oxidation time. The composite prepared by sintering the precursor of manganese benzoate via sol - gel method performed the best in capacity; No big difference in the initial delithiation process was detected between MnO/C composites synthesized with different calcinations duration, but cycling performances and rate capability decrease with the increase of calcinations duration; capacity of composite sintered at 500℃is higher than that of 600℃and 400℃; the delithiation capacity increase while we increase the oxidation time. Therefore, MnO/C composite with best performance could be prepared by isolating precursor of manganese benzoate from air, sintering at 500℃for 2h, cooling to 200℃, and then exposing to air at 200℃for 5h.In addition, the influence of Ni doping on the electrochemical properties MnO/C composite is studied. After doping, de lithiation capacity, cycling performance and rate capability all have different degrees of reduction.
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