Synthesis and electrochemical properties of Li2MnSiO4/C nanoparticles via polyol process

Abstract

Carbon-coated lithium manganese silicate (Li2MnSiO4/C) nanoparticles were synthesized by polyol process. X-ray diffraction (XRD) patterns of the obtained materials exhibit a good fit with that of the Li2MnSiO4 phase. Field emission scanning electron microscopy (FESEM) images of the obtained samples show that the particle size is only tens of nanometers. The high resolution transmission electron microscopy (HRTEM) analysis shows that the Li2MnSiO4 nanoparticles are surrounded by a very thin film of amorphous carbon. The composite prepared through polyol process shows good performance as cathode materials in lithium cells at room temperature. The charge capacity of the Li2MnSiO4/C samples is 219 mAh/g (about 1.3 Li+ per unit formula extracted), and the discharge capacity is 132 mAh/g (about 0.8 Li+ per unit formula inserted) in the first cycle in the voltage range of 1.5–4.8 V. A good capacity cycling maintenance of 81.8% after 10 cycles was obtained.