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[Display omitted] • A 3-dimensional structure comprised of silicon nanoparticles assembled on an nitrogen-doped carbon foam with MXene as the cover layer (MXene@SiNPs@NC foam) is demonstrated. • The MXene layer protects the silicon nanoparticles from directly contacting the electrolyte. • The nitrogen-doped carbon foam and MXene are used as the conductive frame and covering layer, providing effective channels for electron transport/ion diffusion. • The substantial void spaces between the MXene layer and the nitrogen-doped carbon foam skeleton can accommodate the significant silicon nanoparticles volume change during lithiation/delithiation. • The self-standing and binder-free anode was used without a metal current collector. Silicon (Si) is one of the most promising anode materials for lithium-ion batteries (LIBs) because of its high specific capacity. However, the poor cycling stability results from huge volume fluctuation and low intrinsic conductivity, which greatly hinders Si-based anodes development. Herein, we construct a three-dimensional structure comprised of Silicon nanoparticles (SiNPs) anchored on a nitrogen -doped carbon (NC) foam with a covered MXene layer (MXene@SiNPs@NC foam), which acts as a self-standing Si-based anode for high performance LIBs. The design of NC foam as the conductive frame and MXene as the covering layer provides effective channels for electron transport/ion diffusion, and simultaneously allows the anode to adapt to the drastic Si volume change during lithiation/delithiation. The self-standing MXene@SiNPs@NC foam electrode delivers a high specific capacity (1658 mAh g−1 after 100 cycles at 0.1C) and a steady cycling capacity (857 mAh g−1 after 500 cycles at 0.5C). Moreover, a full-cell constructed using MXene@SiNPs@NC foam //NCM 111 exhibits a high gravimetric energy density (433 Wh kg−1). This MXene@SiNPs@NC foam anode with good electrochemical performance renders as a promising candidate for broad LIBs applications. [ABSTRACT FROM AUTHOR]

Currently, with the rise of the photovoltaic industry, how to effectively treat waste silicon powder from an environmentally friendly and economic point of view becomes significant. We reported a simple method to prepare the "core-shell" structure of silicon/carbon nanotubes/carbon (Si/CNTs/C) composite by ball-milling using waste silicon powder. Specifically, The synergistic effect of CNTs and amorphous carbon matrix is beneficial to improving the transmission rate of Li-ions and electrons, and facilitating the reaction kinetics of Li-ions in the process of lithiation/de-lithiation. Meanwhile, the carbon coating layer reduces the direct contact between silicon and the electrolyte, which greatly alleviates the volume expansion of silicon in cycling. With these merits, Si/CNTs/C anode shows high rate performance and outstanding cycling stability up to 300 cycles at 0.2C. Furthermore, full cells assembled with pre-lithiated Si/CNTs/C anodes and commercial NCM811 cathodes deliver considerable initial coulombic efficiency (84.4%) and high energy density (502 Wh kg−1). Si/CNTs/C composites prepared by ball-milling show excellent long-cycle stability and rate performance. [Display omitted] • Industrial waste silicon is used to prepare silicon-based anodes. • Two-step ball milling method to prepare Si/CNTs/C composite. • A solution-based chemical prelithiation method is proposed. • Si/CNTs/C anode exhibits excellent long-cycle stability and good rate performance. • A full cell shows an improved ICE (84.4%) and a higher energy density (502 Wh kg−1). [ABSTRACT FROM AUTHOR]