Li2FeSiO4/C aerogel: A promising nanostructured cathode material for lithium-ion battery applications

Li2FeSiO4/C aerogel is successfully prepared using a high-temperature, high-pressure supercritical drying method. The prepared Li2FeSiO4/C aerogel is annealed at optimum temperature. The structural information is obtained from Powder X-ray diffraction and Fourier transform infrared spectroscopy results. The Li2FeSiO4/C aerogel annealing temperature is fixed at 700 degrees C based on the Thermogravimetric and differential scanning calorimetry. The electrical conductivity of the Li2FeSiO4/C aerogel is calculated using alternating current impedance, and it is 1.4738 x 10(-8) S cm(-1). The presence of carbon and the formation of Li2FeSiO4 is confirmed through Raman analysis. The X-ray photoelectron spectroscopy elemental analysis reveals Si4+, Fe2+, Li+, and C with their respective binding energies. Field emission scanning electron microscopy and transmission electron microscopy images show the formation of randomly distributed tiny particles are linked together within a porous structure. The specific surface area of 59.037 m(2) g(-1) with an average pore diameter of 22.8 nm is measured through N-2 adsorption/desorption isotherm analysis. The electrochemical performance of the Li2FeSiO4/C aerogel exhibits a discharge capacity of 140 mA.h g(-1) at 100 mA g(-1) current density over 130 cycles with 100% coulombic efficiency. Lithium-ion diffusion co-efficient (D-Li(+) = 2.63 x 10(-8) cm(2) s(-1)) is measured from electrochemical impedance spectroscopy. (C) 2021 Elsevier B.V. All rights reserved.