Silicon represents one of the most promising anodes for next-generation Li-ion batteries due to its very high capacity and low electrochemical potential. However, the extremely poor cycling stability caused by the huge volume change during charge/discharge prevents it from the commercial use. In this work, we propose a strategy to decrease the intrinsic volume change of bulk Si-based anodes by preinsertion Li into Si with a chemical reaction. Amorphous Li12Si7 was successfully synthesized by a hydrogen-driven reaction between LiH and Si associated with subsequent energetic ball milling. The as-prepared amorphous Li12Si7 anode exhibits significantly improved lithium storage ability as ∼70.7% of the initial charge capacity is retained after 20 cycles. This finding opens up the possibility to develop bulk Si-based anodes with high capacity, long cycling life and low fabrication cost for Li-ion batteries.

In this work, a novel hexagonal Li2MgSi anode is successfully prepared through a hydrogen‐driven chemical reaction technique. Electrochemical tests indicate significantly improved cycling stability for the as‐synthesized Li2MgSi compared with that of Mg2Si. Ball‐milling treatment induces a polymorphic transformation of Li2MgSi from a hexagonal structure to a cubic structure, suggesting that the cubic Li2MgSi is a metastable phase. The post‐24‐h‐milled Li2MgSi delivers a maximum capacity of 807.8 mAh g−1, which is much higher than that of pristine Li2MgSi. In particular, the post‐24‐h‐milled Li2MgSi retains 50% of its capacity after 100 cycles, which is superior to cycling stability of Mg2Si. XRD analyses correlated with CV measurements do not demonstrate the dissociation of metallic Mg and/or Li–Mg alloy involved in the lithiation of Mg2Si for the Li2MgSi anode, which contributes to the improved lithium storage performance of the Li2MgSi anode. The findings presented in this work are very useful for the design and synthesis of novel intermetallic compounds for lithium storage as anode materials of Li‐ion batteries.

Lithium sulfur (Li–S) batteries have been considerably studied in energy storage systems because of their extremely high energy density. Nevertheless, poor sulfur utilization and lower sulfur loading, polysulfides shuttling, and short cycling life are the major obstacles to their application. Herein, we present the cubic structure of CoS2 microcrystals decorated on Co/N-codoped carbon nanofibers (denoted as CSCNC) by an electrospinning technique followed by a hydrothermal process. The Li2S6 catholyte was added in the fibrous CSCNC network as the current free electrode for Li–S batteries, which was used as the positive catalyst to restrain the shuttle effect and facilitate the reaction kinetics. Additionally, CoS2 and Co are dual functional electrocatalysts for facilitating lithium sulfide nucleation onto the surface of CSCNC, thus reduce electrochemical polarization and enhance the specific capacity. This CSCNC@Li2S6 electrode exhibits 877 mAh g–1 capacity retention with sulfur loading of 7.11 mg over 200 cycles and has an average decay of 0.11% per cycle. Additionally, the composite electrode with sulfur loading accomplishes up to 14.22 mg, providing 12.7 mAh of extremely high capacity, which is much higher than that of the carbon-based electrodes for Li–S batteries.

Liquid-liquid phase separation (LLPS) forms biomolecular condensates or coacervates in cells. Metabolic enzymes can form phase-separated subcellular compartments that enrich enzymes, cofactors, and substrates. Herein, we report the construction of synthetic multienzyme condensates that catalyze the biosynthesis of a terpene, α-farnesene, in the prokaryote E. coli. RGGRGG derived from LAF-1 was used as the scaffold protein to form the condensates by LLPS. Multienzyme condensates were then formed by assembling two enzymes Idi and IspA through an RIAD/RIDD interaction. Multienzyme condensates constructed inside E. coli cells compartmentalized the cytosolic space into regions of high and low enzyme density and led to a significant enhancement of α-farnesene production. This work demonstrates LLPS-driven compartmentalization of the cytosolic space of prokaryotic cells, condensation of a biosynthetic pathway, and enhancement of the biosynthesis of α-farnesene.

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