KOH selective etching synthesis and electrochemical performance of nano porous Li2FeSiO4/C composite

[Display omitted] •Nano porous Li2FeSiO4/C composite (LFS-10S) was prepared by KOH selective etching.•LFS-10S possesses a reduced particle size of about 25 nm.•LFS-10S owns a high surface area of 123.23 m2/g.•LFS-10S delivers a discharge capacity of 235.2 mA h g−1 at a current rate of 0.1 C. Nano porous Li2FeSiO4/C composite (LFS-10S) was prepared by KOH selective etching Li2FeSiO4-(SiO2)0.1/C composites. This method allows directly pore-creating on Li2FeSiO4 crystal. Common porous Li2FeSiO4/C (LFS) were also prepared as a control. LFS-10S and LFS were characterized by XRD, SEM, TEM and nitrogen adsorption/desorption test. XRD analysis shows that the LFS-10S material was composed of crystalline particles with a monoclinic crystal system in the P21 space group. SEM and TEM tests indicate that the particle size of LFS-10S is 20 ∼ 30 nm. The nitrogen adsorption/desorption test shows that the specific surface area of LFS-10S is 123.23 m2/g, larger than that of LFS (71.56 m2/g). These features make LFS-10S exhibit better electrochemical performance over LFS. The specific discharge capacity of LFS-10S at 0.1 C is as high as 235.2 mA h g−1, higher than that of LFS (158.4 mA h g−1). Moreover, the rate performance, cycling performance and lithium ion diffusion coefficient of LFS-10S are all better than those of LFS.