1 Section of Chemistry, The Faculty of Engineering and Science, Aalborg University, VBN2 Department of Chemistry and Bioscience, The Faculty of Engineering and Science, Aalborg University, VBN3 Inorganic Amorphous Materials, The Faculty of Engineering and Science, Aalborg University, VBN4 The Faculty of Engineering and Science, Aalborg University, VBN5 Qilu University of Technology6 Ocean University of China7 Qilu University of Technology8 Ocean University of China
The mesoporous biocarbon coated Li3V2(PO4)3(MBC-LVP) cathode material is synthesized by abiotemplate-assisted sol–gel reaction process using low-cost beer waste brewing yeasts (BWBYs) as bothstructural template and biocarbon source. The structure and electrochemical performances of MBC-LVPwere investigated using Raman spectra, thermogravimetric measurements (TGA), adsorption–desorptionisotherms and pore-size-distribution curves, X-ray diffraction (XRD), transmission electron microscope(TEM and HRTEM), and electrochemical methods. The results show that the MBC-LVP synthesized at750◦C has a hierarchical nanostructure, which consist of Li3V2(PO4)3crystal nanoparticles and amor-phous biocarbons network (11.5%) with hierarchical mesoporous structures (slit shape mesopores, openwormlike mesopores and plugged mesopores). This hierarchical nanostructure facilitates electron andlithium ion diffusion. The MBC-LVP electrode has high discharge capacity (about 205 mAh g−1) at a cur-rent density of 0.2 C in the voltage region of 3.0–4.8 V and the diffusion coefficient of Li+-ions determinedby CV and EIS is higher than those of olivine LiFePO4. We have revealed the formation mechanism of MBC-LVP, the possible lithium pathways in the MBC-LVP and established a relation between the structure andthe ionic and electronic transport properties.