Amorphous Si (a-Si) shows potential advantages over crystalline Si (c-Si) in lithium-ion batteries, owing to its high lithiation potential and good tolerance to intrinsic strain/stress. Herein, porous a-Si has been synthesized by a simple process, without the uses of dangerous or expensive reagents, sophisticated equipment, and strong acids that potential cause environment risks. These porous a-Si particles exhibit excellent electrochemical performances, owing to their porous structure, amorphous nature, and surface modification. They deliver a capacity of 1025 mAh g at 3 A g after 700 cycles. Moreover, the reversible capacity after electrochemical activation, is quite stable throughout the cycling, resulting in a capacity retention about around 88 %. The direct comparison between a-Si and c-Si anodes clearly supports the advantages of a-Si in lithium-ion batteries.

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Amorphous Si (a-Si)s hows potential advantages over crystalline Si (c-Si)i nl ithium-ion batteries,o wingt oi ts high lithiation potential and good tolerance to intrinsic strain/ stress.H erein, porous a-Si has been synthesized by as imple process,w ithout the uses of dangerous or expensive reagents, sophisticated equipment, and strong acids that potential cause environment risks.These porous a-Si particles exhibit excellent electrochemical performances,owing to their porous structure, amorphous nature,a nd surface modification. They deliver ac apacity of 1025 mAh g À1 at 3Ag À1 after 700 cycles.M oreover,the reversible capacity after electrochemical activation, is quite stable throughout the cycling, resulting in ac apacity retention about around 88 %. The direct comparison between a-Si and c-Si anodes clearly supports the advantages of a-Si in lithium-ion batteries.Scheme 1. Synthesis process of porous a-Si anode.

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.

The two‐dimensional (2D) metal‐organic frameworks (MOFs) have capabilities to reduce CO2 with high Faradaic efficiency (FE). Herein, the role of incorporating bimetallic Ni and Fe into newly constructed MOFs is studied. This work highlights the use of bimetallic synergistic effect with surrounded nitrogen atoms, opening new avenues for efficient electrocatalytic reduction of CO2. This MOF Ni‐Fe contains moieties surrounded by four nitrogen atoms via covalent bonding, which resembles the porphyrin‐based molecular units as selective and effective homogeneous CO2 reduction electrocatalysts. Besides, density functional theory (DFT) also helps to figure out that the incorporation combination of metals helps achieve the high FE of 98.2% with stability up to 30 h under a low applied potential of −0.5 V versus reversible hydrogen electrode (RHE). These results offer a promising avenue to develop and optimize the MOFs‐based electrocatalysts for electrochemical conversion of CO2.