fig15

Figure 15. (A) Electrochemical Na⁺ storage capabilities of MGO-Si and crystalline Si. (a) Cyclic performances of MGO-Si and pristine crystalline Si at 50 mA g^-1. (b) Comparison of rate capabilities. (c) Charge/discharge curves of the MGO-Si electrode at different current densities. (d) Long-term cycling stability of MGO-Si at 500 mA g^-1. (B) Investigation of the reaction mechanism of the MGO-Si electrode. (a) Contour plot of ex-situ XRD patterns of the (111) and (200) MGO-Si peaks at different cut-off voltages during the discharge cycles. (b) Ex-situ TEM images and (c) enlarged filtered HR-TEM images of MGO-Si before cycling and when discharged and charged. (d and e) STEM-EELS line scan and corresponding EELS spectra of sodiated MGO-Si. (f and g) TEM line scans of MGO-Si when discharged and charged. Reproduced with permission from^[175]. Copyright © 2023 John Wiley & Sons, Inc.