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Transition metal oxides, especially bimetal oxides, are considered as one of the most promising anode materials for high‐performance lithium‐ion batteries (LIBs) due to their ultra‐high theoretical capacity. However, it is difficult to achieve fast charging at high rates due to the issues of poor electrical conductivity, large volume expansion, and poor reaction kinetics. The design of advanced nanostructured anode materials is very important to boost lithium storage performance. Herein, the multi‐hierarchical heterostructure material NiCo2O4/ZnCo2O4/Carbon Cloth (NCO/ZCO/CC) including carbon cloth substrate, ZnCo2O4 nanosheets, and NiCo2O4 nanowires is prepared as a binder‐free anode for LIBs. Benefiting from the special hierarchical nanostructure and the synergistic interaction of the component, the as‐prepared NCO/ZCO/CC anode material exhibits good electrical conductivity, structural stability, and electrochemical kinetics, which can provide a high reversible areal capacity of 2.55 mAh cm−2 at 2 mA cm−2 after 200 cycles. At a high current density of 5 mA cm−2, the NCO/ZCO/CC electrode only takes about 20 min to fully charge and it can still reach a capacity of 1.50 mAh cm−2 with a capacity retention of 86.2% after 400 cycles, revealing the potential for fast charging at high rates. [ABSTRACT FROM AUTHOR]

Low electronic conductivity and large volume changes during the (de)lithiation process are the two main challenges for ZnO anode materials used for lithium‐ion batteries (LIB). Here, a free‐standing, flexible, and binder‐free LIB electrode composed of ZnO nanorods and carbon cloth (CC) is fabricated. This is then decorated with Ag nanoparticles and finally coated by an amorphous carbon layer to form the hybrid electrode: (C@(Ag&ZnO)). The voids among the nanorods are sufficient to accommodate the volume expansion of the ZnO while the flexible CC, which acts as the current collector, relieves the volume change‐induced stress. The Ag nanoparticles are effective in improving the conductivity. This composite electrode shows excellent LIB performance with a stable long cycling life over 500 cycles with a reversible capacity of 1093 mAh g−1 at a current density of 200 mA g−1. It also shows good rate performance with reversible capacity of 517 mAh g−1 under a high‐current density of 5000 mA g−1. In situ Raman spectroscopy is conducted to investigate the contributions of the amorphous carbon layer to the capacity of the whole electrode and the synergy between the CC and ZnO nanorods. [ABSTRACT FROM AUTHOR]

A yolk structure of C/SiO 2 /C and a hollow structure of C/SiO 2 composites with porous feature are synthesized by one-step method and two steps method, respectively. When evaluate as an anode material for lithium-ion batteries (LIBs), the C/SiO 2 /C and C/SiO 2 deliver an impressive cycle performance and exhibit an excellent rate capacity. More importantly, attributing to the one-step synthesis method of C/SiO 2 /C, it possesses interconnected micropore and higher special surface area, which provide a more efficient ionic transportation path and facilitate the diffusion of Li + between the electrolyte and C/SiO 2 /C, thus the activation time of SiO 2 can be effectively shorten. The capacity achieves the steady value of 1135 mAh g −1 (based on the weight of SiO 2 in the electrode material) only by 60 cycles at 50 mA g −1 which is much faster than that of C/SiO 2 and delivers a high-rate capacity of 390 mAh g −1  at 1000 mA g −1 . Considering the good lithium storage abilities and fast-activated features, the C/SiO 2 /C composites hold promise in applications in practical LIBs. [ABSTRACT FROM AUTHOR]

In order to improve electrochemical performance of inert SiO anode for lithium ion batteries, submicro-sized porous SiO/C and SiO/C/graphene spheres with the same SiO content (43 wt.%) have been synthesized through a simple suspension nebulization and spray pyrolysis method followed by carbonization, where the components of the spheres are mixed uniformly. The addition of graphene results in mesoporous structure of the SiO/C/graphene spheres. The electrochemical performances of the porous SiO/C and SiO/C/graphene spheres have been evaluated, which indicate that the SiO/C/graphene spheres exhibits much higher cyclic capacity and stability than SiO/C with reversible capacity retention of 97% over 100 cycles. The graphene additives display very strong effects in reducing charge transfer resistance and improving structural stability of the porous spheres simultaneously. The mesoporous SiO/C/graphene spheres are promising anode candidate for high energy-density lithium ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: Rutile structure SnO2 nano-single crystals have been synthesized using tin (IV) chloride as precursor by the modified hydrothermal method. Controllable morphology and size of SnO2 could be obtained by adjusting the concentration of the hydrochloric acid. The SnO2 nanoparticles were characterised by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and electrochemical methods. The SnO2 nanoparticles as anode materials in lithium-ion batteries exhibit high lithium storage capacities. The reversible capacities are more than 630 mA h g−1. [Copyright &y& Elsevier]

Here, we report a nano-sized red phosphorous/biomass-derived porous carbon (P@BDPC) which is employed as anode materials for lithium ion batteries (LIBs) via a facile vaporization−condensation−conversion strategy (VCC) with tobacco stem as the carbon precursor. The biomass-derived porous carbon not only acts as the host of red phosphorus to enhance the electrical conductivity, but also minimizes the volume expansion (≈400%) during cycling. The obtained P@BDPC composite with a high red phosphorus content (62.1 wt%) delivers a high specific capacity of 1689 mA h g−1 at 500 mA g−1 with an initial Coulombic efficiency (ICE) of 91.7% and superior rate capability of 599 mA h g−1 at 30 A g−1. Furthermore, a high reversible capacity of 918 mA h g−1 can be retained over 600 cycles at 5 A g−1, indicating a remarkable cycle stability. More importantly, the introduction of agriculture waste-tobacco stem contributes to building low-cost, high-performance anode materials. Synthetic route of the P@BDPC. Image 1 • Red P was successfully confined to nanoscale in N-doped porous carbon matrix. • The N-doped porous carbon ensures solid capture of red P and fast ion diffusion. • The red P/carbon composite exhibits superior specific capacity and rate capability. • A long cycle-life of 918 mA h g−1 at 5 A g−1 after 600 cycles was also achieved. [ABSTRACT FROM AUTHOR]

Abstract A unique double core-shell structure of Si@PANI@TiO 2 nanocomposite is synthesized by a simple in-situ growth method. The two shells of polyaniline (PANI) and TiO 2 , hand in hand, play a key role to improve the electrochemical performance: First, the flexible properties of polyaniline (PANI) effectively accommodate the volume change of Si during the cycling. Second, the good mechanical feature of TiO 2 can maintain the structural integrity and attenuate the volume expansion of Si cores. Finally, both of polyaniline and the lithiated TiO 2 enhance the conductivity of Si, which promotes the electrons transport. Resulting in the Si@PANI@TiO 2 double core-shell nanocomposite exhibits remarkable synergy in large, reversible lithium storage, delivering a reversible capacity as high as 1027 mAh g−1 after 500 cycles and a superior rate capacity of 640 mAh g−1, at a current of 500 and 4000 mA g−1, respectively. This excellent cycling and high-rate capability can be ascribed to the unique and well-designed double core-shell structure with the synergistic effect between polyaniline (PANI) and TiO 2. Graphical abstract Image 1 Highlights • Double core-shell of Si@PANI@TiO 2 was prepared by a simple in-situ growth method. • PANI and TiO 2 shell played the important role for buffering the volume expansion of SiO 2. • TiO 2 shell maintain the integrity of the material structure. • PANI and the Lithiated TiO 2 improved the conductivity of Si. • Excellent cycling stability and superior rate capacity were demonstrated. [ABSTRACT FROM AUTHOR]

MXene has been recognized as a promising anode for sodium-ion batteries (SIBs) owing to its high electrical conductivity and long-term durability. But the low energy density and agglomeration-prone nature extensively preclude their application similar to that of other two-dimensional (2D) materials. This work transformed 2D MXene to a three-dimensional (3D) conductive network by incorporating Sn and Sn 4 P 3 nanoparticles between the MXene sheets. The homogenous distribution of ultrasmall Sn nanoparticles (∼4 nm) ensures a highly conductive network not only along the MXene planes but also perpendicular to them, while the covalent-bonded Sn 4 P 3 nanoparticles significantly reinforce the structural stability. Additionally, in/ex situ characterizations reveal a considerably high reversibility of the Na+ insertion/extraction process in the network. Benefiting from the rational design, the 3D conductive network yields an enhanced capacity, long-term cycling stability (127.2 mAh g−1 after 1000 cycles at 5 A g−1), and superior pseudocapacitive properties. • Tin and tin phosphide prevent MXene sheets from stacking. • Metallic Sn improves the conductivity perpendicular to the MXene planes. • The Sn-rich environment effectively activates tin phosphide electrochemically. • Enhanced cyclic stability is obtained over 1000 cycles at 2 and 5 A g−1. [ABSTRACT FROM AUTHOR]

• Four types of Si/G composites with the same components and different combination ways are prepared by simple methods. • Four types of Si/G composites are prepared to study the internal factors affecting the initial coulombic efficiency. • The Si-G@C with large specific surface area still owns the highest initial coulombic efficiency. Investigating the internal factors that affect the initial coulombic efficiency (ICE) of silicon/graphite (Si/G) composites and improving ICE are critical to promote applications of Si/G composites in lithium-ion batteries. Here, four types of Si/G composites are prepared with different specific surface area, Si–G phase interface and charge transfer impedance (R ct) to study the internal factors affecting the ICE of Si/G composites. The experimental results show that the influencing factors on ICE of Si/G composites are not only specific surface area, but also the Si–G phase interface and R ct. During the first lithiation process of Si/G composites, there are some reversible phase (Li x Si, Li x C) and irreversible phase (Li 2 O, Li 2 SiO 4 and organolithium) formed, the ICE of Si/G composites is mainly determined by the irreversible phase. The specific surface area, R ct and Si–G phase interface can affect the reaction kinetics of the materials and the ratio of reversible/irreversible phase content, which ultimately affect the ICE of Si/G composites. A smaller specific surface area and well Si–G phase interface with a low R ct will bring a higher ICE of Si/G composites. This report may provide a new idea for the research of ICE of Si/G composites and promote their practical application. The Si–G, Si–G@C, Si@C–G and Si@C–G@C composites are prepared with different specific surface area, Si–G phase interface and charge transfer impedance (R ct) to study the internal factors affecting the ICE of silicon/graphite composites. The Si–G@C with large specific surface area still owns the highest ICE, due to the well Si–G phase interface and a low R ct , which can affect the reaction kinetics to generate more reversible phase (Li x Si, Li x C) and less irreversible phase (Li 2 O, Li 2 SiO 4 and organolithium). Image, graphical abstract [ABSTRACT FROM AUTHOR]

• g-C 3 N 4 /carbon hybrid cages were rationally designed and fabricated as sulfur host. • Core-shell structured S@g-C 3 N 4 /carbon cathode exhibited excellent cyclic stability. • The shuttle effect was efficiently suppressed by the N-rich host material. • 91% of theoretical capacity of sulfur was achieved in the initial discharge at 0.2 C. • A capacity of 636 mAh g−1 was obtained after 400 discharge/charge cycles at 1 C. To compete with commercial lithium-ion batteries, light-weight, conductive and polar hosts with high sulfur loading content are required for lithium-sulfur batteries. Herein, light-weight g-C 3 N 4 /carbon hybrid cages as sulfur host have been designed and fabricated using NaCl and nanosized manganese compounds (MnO and MnCN 2) as templates via a facile and controllable aerosol-pyrolysis route. The porous g-C 3 N 4 /carbon shell is designed to facilitate fast electron/Li ion transports and impede lithium polysulfide shuttle simultaneously. The cage cavity created by the NaCl template is designed to enhance sulfur loading content. Electrochemical evaluations demonstrate excellent cyclic capacity and stability of core-shell structured S@g-C 3 N 4 /carbon cathode endowed by the versatile structural and chemical advantages of the g-C 3 N 4 /carbon host cages. The first-cycle discharge capacities reach 1517 and 1240 mAh g−1 at 0.2 C and 1 C, respectively, demonstrating efficient utilization of the loaded sulfur. The capacity fading rate of each cycle is 0.09% during 400 discharge/charge cycles (from the second cycle) at 1 C. These light-weight, conductive and polar g-C 3 N 4 /carbon cages have been demonstrated to be suitable hosts to load sulfur as high-performance cathode for lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]