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High‐entropy spinel oxides (HESOs) are a promising anode material for lithium‐ion batteries (LIBs) due to their high structural stability and theoretical capacity. However, the development of HESOs is mainly limited to five‐component equimolar systems, and the lithium‐storage mechanism is still controversial. A nonequimolar six‐component oxide, (CoMnZnNiMg)2CrO4, is synthesized using a solution combustion method. The prepared material is a HESOs, consisting of homogeneous nanoparticles with a mesoporous structure. (CoMnZnNiMg)2CrO4 exhibits high rate performance (371 mAh g−1 at 2000 mA g−1) and long cycling stability (608 mAh g−1 after 200 cycles at 200 mA g−1). A variety of constituent elements exist uniformly and stably in a spinel phase due to the high‐configuration entropy‐induced phase‐stabilization effect, and the synergistic effect of the various valence elements in the material results in the excellent electrochemical performance. The outstanding electrochemical kinetic properties of the HESOs are mainly attributed to the high‐ionic‐diffusion coefficients and pseudocapacitance contributions. In addition, the HESOs electrodes undergo an amorphous conversion during the initial charge/discharge process. It is shown that the rational design and modulation of the active component is an effective way to obtain high‐performance HESOs for LIBs. [ABSTRACT FROM AUTHOR]

The main obstacles to the development of manganese-based oxide anode materials for lithium-ion batteries (LIBs) are inherently low conductivity and sluggish electrochemical kinetics. In this work, we propose a strategy of introducing oxygen vacancies (Vö) on the surface of nanostructure at room temperature and atmospheric pressure to improve the electrochemical performance of anode materials. Porous MnO2 spheroids with 11.2% Vö are fabricated by a ball milling method using commercial electrolytic MnO2. The as-synthesized MnO2 is composed of 20–30 nm nanoparticles. The optimized MnO2 shows an excellent rate capability of 350 mAh g−1 at 6.4 A g−1 and high specific capacity of 1200 mAh g−1 after 650 cycles under 2 A g−1. The boosted electrochemical performance is attributed to the porous hierarchical structure and the appropriate Vö concentration involved in the MnO2. In addition, the enhanced Li+ diffusion coefficient is demonstrated through the kinetics analysis. The approach provides a facile route via tunable Vö concentration for improving the electrochemical performance of manganese-based oxide anode materials for LIBs. Highlight: • The porous MnO2 spheroids with tunable Vö concentrate were synthesized by a ball milling method. • The MnO2 spheroids are composed of 20-30 nm nanoparticles. • The MnO2 spheroids exhibit an excellent rate performance and cycling stability. • The ball mill is facile, environmentally friendly, economical for the mass industrial scale. [ABSTRACT FROM AUTHOR]

The traditional MoSe 2 anode material for lithium-ion batteries has poor cyclic stability and relatively low capacity, which hinders its practical application. Herein, high capacity of Si and Se are exploratively incorporated into two-dimensional MoSe 2 nanopetals to configure Se@MoSe 2 /Si composite. The optimized Se@MoSe 2 /Si composites have both high capacity and good electrochemical stability with a high retention capacity of 1187.7 mAh/g after 200 cycles at 100 mA/g current density. The visible depression on volumetric expansion is observed on the configuration of Se@MoSe 2 /Si. The admirable function of silicon on the enhancement of the electrochemical activity and the conductivity of Se@MoSe 2 is theoretically demonstrated by First-principles calculations. This mutually beneficial interaction between the components demonstrates a promising synergistic effect on Se@MoSe 2 /Si. [ABSTRACT FROM AUTHOR]

Layered metal sulfides are potential anode materials for lithium-ion batteries (LIBs) because their unique structure makes them suitable for Li+ de-intercalation. As a typical 2D layered material, MoS 2 is a potential anode material for LIBs due to the weak van der Waals forces between the layers, which facilitates the de-intercalation of Li+ and supports multiple Li+. However, when MoS 2 is used as anodes for LIBs material, rapid capacity decay hinders the application. Coupling two different materials to form a heterogeneous structure is an effective way to solve the above problems. In this work, one-pot hydrothermal method is proposed to construct MoS 2 /SnS heterostructure composites. The electrochemical properties are significantly enhanced, which could be attributed to the presence of heterogeneous structures, leading to increase the electrode charge transfer rate and interfacial reaction kinetics. The results show that the discharge capacity of the MoS 2 /SnS-1.5 electrode is about 1492.1 mAh/g at 500 mA/g. Furthermore, assembled MoS 2 @SnS-1.5||LiCoO 2 full cell displays a high discharge capacity of 226.1 mAh/g after 50 cycles at 500 mA/g. This facile method provides the application value of layered metal sulfides as LIBs anode materials. We have used a one-pot hydrothermal method to prepare MoS 2 @SnS heterostructures with flower-like MoS 2 and sheet-like SnS tightly bound. When used as an anode for lithium-ion batteries, MoS 2 /SnS-1.5 electrode delivers excellent rate performance and high capacity (1597.3 mAh/g under a current density of 500 mA/g after 100 cycles), which are attributed to the presence of heterogeneous structures. [Display omitted] • MoS 2 /SnS material is prepared by hydrothermal synthesis method. • The electrode possesses the best electrochemical performance at 1.5 mmol (SnCl 4). • The MoS 2 /SnS heterostructures increase the charge transfer rate and interfacial kinetics. • The MoS 2 /SnS-1.5 electrode displays superior lithium-ion storage performance. [ABSTRACT FROM AUTHOR]

P/Se@C composites were configured with multiple bonding interface consisting of highly P/Se heterogeneous structure and admirable P C, Se C bonding to achieve outstanding pseudocapacitive effect and fast lithium-ion/electron diffustion. [Display omitted] Due to its large capacity in theory, red phosphorus (RP) has become a viable anode choice for lithium-ion batteries (LIBs), but because of its inherent attributes, for instance, substantial volume expansion during cycling, which causes capacity degradation and electrode pulverization, it is difficult to use in real applications. To address these challenges, this study investigates the modification of red phosphorus-based electrodes through P/Se heterointerface engineering and conductive network design. The theoretical calculation shows that the introduction of selenium reduces the band gap of P/Se. While forming the P/Se heterogeneous interface enhances the cyclic stability of the composites, it simultaneously boosts the surface pseudocapacitive effect of the materials. The introduction of activated carbon builds an admirable conductive network. The resulting composite electrode, denoted as P/Se@C, exhibits promising electrochemical performance. After 800 cycles, P/Se@C composite retains a stable capacity of 541.1 mAh/g at 200 mA g−1. Furthermore, even after 1500 cycles, P/Se@C composite retains a capacity of 408.3 mAh/g at 1000 mA g−1. [ABSTRACT FROM AUTHOR]

An unconventional spheric quasi-SEI film is strategically configured on cost-effective red phosphorus. Highly activated surface with weakened P P bond strength and strengthened binding force increase the electrode integration. [Display omitted] • A method for moderate phosphorylation and etching of phosphorus surface. • An unconventionally spheric quasi-SEI film forms before lithiating progress. • Balls change from solid core–shell structure to hollow core–shell sphere structure. • Highly activated surface with weakened P P bond strength. • Highly activated surface strengthened binding force of PVdF. Solid electrolyte interface (SEI) film is the most important separation layer between nonaqueous electrolytes and anodes to protect anode from corrosion and maintain continuous ionic diffusion tunnels. However, SEI film, especially for high-capacity anode materials, is still confined to continuous and stable ionic conductive layer despite the conventional SEI film is intrinsically poor to resist against the drastic volumetric changes of active centers. Herein, an unconventional spheric quasi-SEI film is thus strategically configured on cost-effective red phosphorus electrode materials by moderate phosphorylation combined with pore-forming process. Microstructure adjustment from solid microspheres structure to hollowed core–shell spheres is visibly taken place on this amazing spheric quasi-SEI film during the stabilization. Benefiting from the highly activated surface with weakened P P bond strength and the strengthened binding force between phosphorus and binders, the optimized phosphorus anode presents an outstanding long-term durability with a high discharge capacity of 1126.4 mAh/g over 400 cycles at 200 mA g−1 even at a high phosphorus load ratio of 70 wt%. This revolutionary configuration of quasi-SEI film provides high-capacity anode materials subject to large volumetric changes an unconventional approach from dependence on conductive framework/matrix. [ABSTRACT FROM AUTHOR]

Graphite carbon for lithium-ion batteries (LIBs) has received extensive attention due to the strong stability and moderate working potential. In spite of these advantages, the intrinsic low theoretical capacity and the poor interface compatibility severely restrict the practical application of graphite carbon. Herein, a rational strategy to improve lithium storage performance of carbon derived from metal organic frameworks (MOFs) is constructively employed by decorating with red phosphorus. Because of the unique structure and properties, nickel MOFs-derived micro flower carbon matrix can not only provide more active sites for lithium storage, but also facilitate the performance of red phosphorus sites. Furthermore, the carbon decorated with red phosphorus (P/Ni@C) are tightly anchored by P-O-C bonds to provide a guarantee for the synergistic effect. The P/Ni@C anode delivers a high discharge capacity of 1184.6 mAh g−1 over 400 cycles at 200 mA g−1 and high-rate capacity of 686.8 mAh g−1 at 2000 mA g−1, which demonstrate excellent cyclic stability and charge transfer kinetics, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

• We propose coating the hollow MnO 2 microspheres with Fe 2 O 3 nanoparticles to form a protective layer. • The composite microspheres exhibit excellent rate capability of 296.2 mA h g-1 at 6.4 A g -1. • The spherical morphology of MnO 2 @Fe 2 O 3 with good fluidity is more beneficial to the electrode coating process of LIBs. Manganese dioxide (MnO 2) anode materials with high energy and power density have attracted wide attention in lithium-ion batteries (LIBs). However, the poor rate capability and inferior cycling stability hindered their commercial applications. To address the issues, we designed and synthesized MnO 2 @Fe 2 O 3 composite microspheres by a solvothermal treatment and subsequent annealing process, on which Fe 2 O 3 nanoparticles are coated on the surface of MnO 2 microspheres with a diameter of about 2 µm. The Fe 2 O 3 thin protective film on the surface of MnO 2 alleviates the volume change of MnO 2 and the dissolution of Mn element during cycling, and improves the Li+ diffusion coefficient of the electrode materials through the kinetics analysis. The MnO 2 @Fe 2 O 3 microspheres deliver excellent rate capacity of 296.2 mA h g −1 at a high current density of 6.4 A g −1, and superior reversible capacity of 675.4 mA h g −1 and 784.6 mA h g −1 after 150 cycles at 100 mA g −1 and after 1000 cycles at 500 mA g −1, respectively. The enhanced electrochemical performance is attributed to the synergistic effect of different components. The results indicate that MnO 2 @Fe 2 O 3 composite microspheres will be a promising anode materials for superior performance in LIBs. [ABSTRACT FROM AUTHOR]