Metal–Organic Frameworks‐Derived Mesoporous Si/SiO_x@NC Nanospheres as a Long‐Lifespan Anode Material for Lithium‐Ion Batteries

Abstract

Silicon (Si)‐based anode materials with suitable engineered nanostructures generally have improved lithium storage capabilities, which provide great promise for the electrochemical performance in lithium‐ion batteries (LIBs). Herein, a metal–organic framework (MOF)‐derived unique core–shell Si/SiOx@NC structure has been synthesized by a facile magnesio‐thermic reduction, in which the Si and SiOx matrix were encapsulated by nitrogen (N)‐doped carbon. Importantly, the well‐designed nanostructure has enough space to accommodate the volume change during the lithiation/delithiation process. The conductive porous N‐doped carbon was optimized through direct carbonization and reduction of SiO2 into Si/SiOx simultaneously. Benefiting from the core–shell structure, the synthesized product exhibited enhanced electrochemical performance as an anode material in LIBs. Particularly, the Si/SiOx@NC‐650 anode showed the best reversible capacities up to 724 and 702 mAh g−1 even after 100 cycles. The excellent cycling stability of Si/SiOx@NC‐650 may be attributed to the core–shell structure as well as the synergistic effect between the Si/SiOx and MOF‐derived N‐doped carbon.

Green and Scalable Fabrication of Sandwich-like NG/SiOx/NG Homogenous Hybrids for Superior Lithium-Ion Batteries

“…Therefore, two broad diffraction peaks located around 25° and 45° in G/SiO x /G and NG/SiO x /NG could be assigned to the superimposed diffraction peaks of SiO x and rGO. Generally, SiO would be decomposed into Si and SiO 2 under heat treatment [ 14 , 36 , 37 ]. In this work, no diffraction peaks assigned to Si can be observed, which can be attributed to the small crystalline size of Si.…”

The Latest Trends in Electric Vehicles Batteries

“…In recent years, research on composite Si anodes has mainly followed the core/shell and yolk/shell approach towards designing electrodes with superior capacity retention and/or rate performance [ 88 , 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112 , 113 , 114 ]. In Figure 19 , it is possible to identify both design strategies.…”

Progress and Perspective of Metal‐ and Covalent‐Organic Frameworks and their Derivatives for Lithium‐Ion Batteries

“…A full cell based on GeÀ Zn alloy also delivered high energy density and long cycle life (400 cycles), indicating the great potentials for large scale applications. Some other nanocomposites of metal or semi-conductor with carbon matrix, prepared from MOF precursors, have also demonstrated enhanced electrochemical properties, such as ZIF-8 derived Sn@N-MCM, [178] mesoporous Si hollow nanocubes (m-Si HCs), [179] mesoporous Si/SiO x @N-doped carbon spheres, [180] Si@SiO x /C nanoarchitecture, [181] cross-linking Sn-based MOF coated Si composites (Si@Sn-MOF) [19,177] and ball-cactus-like NiÀ SnÀ P@C-CNT [182] (in Figure 8c).…”