Concurrent Ce doping and in-situ carbon coating of Li2MnSiO4 nanoparticles with enhanced capacity via a rapid microwave-assisted sol-gel proces

We demonstrate a straightforward microwave-assisted sol-gel (MSG) process to facilely control the crystallization, ion doping and surface carbon coating synchronously for Li₂Mn_1−xCe_xSiO₄@C (0 ≤ x ≤ 0.05) nanoparticles (NPs) through tuning the velocity of inner gas and the microwave power. In our procedure, Ce³⁺ ions are used as dopants and play a significant role in the microwave absorbent enhancement, and L-Ascorbic acid is used as the carbon source and the effective reductant to prevent the oxidization of Mn²⁺. Upon the MSG process, concurrent incorporation of Ce³⁺ ions into the lattice sites of Li₂MnSiO₄ and the in-situ carbonization of carbonaceous precursors can readily proceed. The optimal Li₂Mn_0.97Ce_0.03SiO₄@C NPs with a narrow particle size distribution in the range of 15–30 nm are demonstrated to show a high initial discharge capacity ~210.5 mAh⋅g⁻¹ at 0.1C with a coulomb efficiency ~90%, and excellent rate performances at various current densities in the voltage range of 1.5-4.5 V.