Tailoring the morphology of orthorhombic Li2MnSiO4 by carbon additive and its impact on transport and Li-storage properties

Carbon additive is an exciting approach for tailoring the surface morphology and improving the material's structural stability, electrical conductivity, and interface chemistry for achieving high capacity and long cycling stability simultaneously. Herein, we successfully introduce sucrose as a carbon additive to tailor the morphology of Li2MnSiO4 (LMS). The low-temperature hydrothermal synthesis route is adopted for preparing pure phase LMS/C-x (x = 0, 2, 5, 7, and 10 wt % refereed as PLMS, LMSC2, LMSC5, LMSC7 and LMSC10). FE-SEM and HR-TEM analyses are used to monitor the changes in the morphology of LMS/C-x composites. The one-dimensional nanorods (formed by the addition of carbon additives) embedded in the as-synthesized best composite sample (LMSC7) are found responsible for the fast lithium-ion diffusion, reactivity, and enhancing the electronic conduction from 26% to 67%, almost three times higher than PLMS. The electronic conductivity of LMSC7 is calculated to be 3.93 x 10(-8) (+/- 0.001) Scm(-1). It also exhibits an initial charge capacity of 240 (+/- 5) mAhg(-1), which is found to be similar to 66% higher than PLMS (90 +/- 5) at 10 mAg(-1) current density at ambient temperature. Furthermore, after a few early cycles, the cyclability profile of LMSC7 demonstrates excellent 100% coulombic efficiency.

Automated summary

Carbon additive, sucrose, was introduced to tailor the morphology of Li2MnSiO4. The addition of sucrose resulted in the formation of one-dimensional nanorods in the composite, which significantly improved the electronic conduction, lithium-ion diffusion, and reactivity. The composites exhibited a high initial charge capacity and excellent coulombic efficiency.