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Silicon has emerged as a prominent candidate for anodes in advanced lithium-ion batteries due to its exceptional theoretical capacity and low operational potential. Despite its advantages, silicon-based anodes face significant challenges, including substantial volume changes, formation of an unstable solid-electrolyte interphase (SEI) film, and voltage hysteresis during lithium alloying/dealloying, which compromise their cycling stability. This study introduces a novel ferrous fluorosilicate (FeSiF6)-modified silicon-based composite anode. FeSiF6 is prepared via a simple reaction between Fe–Si alloys and hydrofluoric acid (HF). Various treatment methods are employed to create modified silicon-based composites with different compositions and morphologies. This innovative composite material prevents the formation of crystalline Li15Si4 and facilitates the formation of a stable SEI film, thereby markedly improving the cycling stability of the silicon-based anodes. Among these, the composite material Fe–Si@F@C (consisting of Fe–Si alloy@FeSiF6@graphite) demonstrates a stable discharge capacity of 975 mA h g−1 after 200 cycles at 1 A g−1, with ∼94% capacity retention, and outstanding rate performance (664.4 mA h g−1 at 4 A g−1). In comparison, the Fe–Si alloy/graphite anode without FeSiF6 shows a much lower discharge capacity of 458 mA h g−1 at 1 A g−1 after 200 cycles and 291.8 mA h g−1 at 4 A g−1. These findings underscore the critical role of FeSiF6 in modifying silicon-based anodes and enhancing their cycling stability, significantly increasing their potential for commercial application in next-generation lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Ammonium polyphosphate (APP) is often used to construct intumescent flame retardant systems together, but it is faced with the problem of adding too much flame retardant. This paper envisions the construction of a modified APP flame retardant (TR@ZIFAPP) with a sandwich structure by the method of covering, which, in order to endow APP flame retardant with better flame retardant effect. By constructing a metal catalytic layer and a triazine carbon formation layer, the modified APP flame retardant has both catalytic carbon formation and phosphorus–nitrogen synergistic flame retardant functions. TR@ZIFAPP is expected to be used in flame‐retardant polymer composites with low addition requirements, adding it to epoxy resin (EP) reveals that the TR@ZIFAPP flame retardant could achieve the optimal flame retardant effect when the addition amount was only 3 wt%. The UL‐94 rating reached V‐0 grade, and the two off‐fire auto‐ignition time levels were only 0.7 s. The analysis of its flame retardant mechanism showed that the flame retardant in EP was mainly through the rapid formation of carbon to isolate oxygen and dilute the flammable gas to reach a strong flame retardant effect. [ABSTRACT FROM AUTHOR]

To further enhance the fire safety of epoxy resins, a phosphorus–nitrogen synergistic flame retardant (DPVHD) with a flexible chain segment and a nitrile group was synthesized. In addition to the traditional flame retardant elements P and N, the flame retardancy of the epoxy composites is further enhanced by the cross‐linking effect of the nitrile groups introduced to form an interpenetrating network with the epoxy matrix. The results showed that the sample with 10 wt% DPVHD‐10/EP had a LOI of 32.3% and passed the UL‐94 V‐0 rating, with PHRR and THR reduced by 15.4% and 47%, respectively, compared to pure EP. It is worth noting that the introduction of flexible chain segments improves the flexural properties of the epoxy resin matrix. Compared with pure epoxy, the flexural properties of epoxy‐cured compounds with DPVHD addition show a rising trend with the increase of flame‐retardant additive. And the rise of DPVHD‐10/EP reaches 33.6%, which greatly reduces the negative effect of flame‐retardant additives on the mechanical properties of the epoxy resin matrix. This work therefore provides new ideas for exploiting the advantages of phosphorus‐nitrogen synergy and nitrile‐based cross‐linking for flame retardancy in epoxy resins. [ABSTRACT FROM AUTHOR]

Due to the high theoretical lithium storage capacity and moderate voltage platform, silicon is expected to substitute graphite and serves as the most promising anode material for lithium‐ion batteries (LIBs). However, substantial volume change during cycling subjects the silicon anode to electrode pulverization and conductive network damage, extensively limiting its commercial purpose. Strategies, such as alloying, nano‐crystallization, and compositing, are developed against these problems. This review introduces the attractive alloying modification method and summarizes the recent advances in microstructure‐engineered silicon alloy anodes for LIBs. The electrochemical performances of silicon alloy anodes with various morphologies, such as nanoparticles, nanowires, two‐dimensional layered structures, porous structures, and thin films, are discussed in detail. The challenges for the commercial application of silicon alloy anodes are elaborated in the end. This review provides a comprehensive overview and concerns of microstructure‐engineered silicon alloy anodes for potential applications in LIBs. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of CO2 into value-added chemicals has been envisioned as a promising strategy to alleviate the issue of increasing CO2 emissions. However, the sluggish oxygen evolution reaction (OER), as the anodic reaction, typically consumes approximately 90% of the electricity input, necessitating the development of an efficient OER for energy-saving purposes. Herein, we developed a unique heterostructure of multi-double (bi)-shelled Co-based spheres via a facile template-free method, in which each bi-shelled structure is composed of Co9Se8/Co9S8/CoO (Co-S-Se) with a symmetric configuration. These heterogeneous nanospheres possess both sufficient heterointerfaces and a high density of active sites and exhibit excellent OER activity in alkaline media with a low overpotential of 226 mV at 10 mA cm−2, a small Tafel slope of 46.5 mV dec−1, and long-term durability over 15 h. As a proof and concept, when coupled with a cathodic CO2 reduction reaction, the electrochemical performance of Pd nanosheets (NSs) for CO2 reduction can be significantly enhanced in terms of product selectivity and energy input. Our study might provide insight into the development of efficient OER electrocatalysts for practical CO2 reduction reactions.Carbon ultilization: Promoting CO2 conversion using low-cost OER electrocatalysts An easy-to-synthesize nanomaterial can improve the economics of recycling carbon dioxide (CO2) into valuable chemicals. Most approaches to CO2 conversion require a charged metal electrode to catalyze removal of an oxygen atom from the gas. Yu Zhang from the East China University of Science and Technology in Shanghai and co-workers have identified a promising low-cost catalyst for this process. Using simple chemical procedures that create nanostructures without needing external templates, the team synthesized multi-bishelled cobalt-based nanospheres with each bi-shelled structure consisting of symmetric heterogeneous configuration. Electrolysis experiments revealed the nanospheres as OER catalysts required lower operating voltages than expensive commercial catalysts such as mesh platinum wire and also generated few by-products. The team’s theoretical calculations indicated that exposed cobalt–sulfur–selenium surfaces lowered energy barriers associated with the oxygen evolution reaction.We developed multi-bishelled cobalt-based nanospheres with each bi-shelled structure consisting of symmetric heterogeneous configuration. This architecture features sufficient heterointerfaces and a high density of active sites benefiting from interfacial electronic modulation. When they worked as OER electrocatalysts in CO2 electrolysis, the electrochemical performance of Pd nanosheets (NSs) for CO2 reduction can be significantly enhanced in terms of product selectivity and energy input. [ABSTRACT FROM AUTHOR]