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Transition metal oxides (TMOs) are potential anode materials for lithium‐ion batteries (LIBs) owing to their superior theoretical capacities, environmental benignity and abundant supply. However, because of the intrinsically poor conductivity, inevitable volume variation, inferior capacity and cyclic stability, the progress of TMOs in practical application is seriously hindered. In this study, a new N‐doped carbon concave‐dodecahedron has been successfully manufactured through a facile method utilizing bimetallic zeolitic imidazolate framework (ZnCo‐ZIF) as both precursor and sacrificial template, in which ultrafine ZnO/Co3ZnC nanoparticles uniformly distributed on the surface can provide additional active sites to effectively accelerate the diffusion of lithium ions. As a result, the as‐prepared ZnO/Co3ZnC/C (ZCC) anode exhibits outstanding mechanical tolerance during lithiation process. Attributed to the superior structure and compositional optimization, the ZCC anode achieves remarkable electrochemical performance with considerable high‐rate capacity (424 mAh g−1 at 2.0 A g−1) and ultralong cyclability (942 mAh g−1 at 0.2 A g−1 after 300 cycles). [ABSTRACT FROM AUTHOR]

CoP and N, O, P triple-doped carbon composites were prepared by low-temperature tandem reaction using MOF as a self-sacrificial template, and their lithium storage properties and mechanisms were investigated. [Display omitted] • The formation of dispersed cubic structure facilitates electrolyte penetration and Li+ diffusion. • Heteroatoms doping adjusts the local electric field of the anode improving the reactivity of the material. • Transformation of the mechanism of CoP anode before and after cycling was confirmed by ex-situ techniques. • Theoretical calculations demonstrate the synergistic effect between the co-doped carbon layer and CoP. Cobalt phosphide (CoP) with high theoretical capacity as well as ceramic-like and metal-like properties is considered as a promising anode for lithium-ion batteries (LIBs). However, the large volume change and sluggish kinetic response limit its practical application. The optimization of composition, structural control and performance regulation of CoP electrodes can be achieved by the bottom-up assembly technique of metal–organic frameworks (MOFs). Due to the effective electronic regulation and lithiophilicity brought by the multiple heteroatoms doping and the synergistic effect of the unique structure derived from MOFs, the N, O, P triple-doped carbon and CoP composites (ZCP@NOP) exhibited excellent rate capability (554.61 mAh g−1 at 2 A g−1) and cycling stability (806.7 mAh g−1 after 500 cycles at 0.5 A g−1). The essence and evolution of lithium storage mechanism in CoP electrodes are also confirmed by the ex-situ techniques. The synergistic benefits of heteroatom co-doping carbon and cobalt phosphide, such as the decrease of the diffusion energy barrier of Li-ions and the optimization of electronic structures, are highlighted in theoretical calculations. In conclusion, new thoughts and ideas for the creation of future battery anode are provided by the combination of the N, O, P co-doping and the adaptable structural adjustment technique. [ABSTRACT FROM AUTHOR]

MOFs derived Zn 3 V 2 O 8 exhibits an excellent specific capacity for highly efficient lithium-ion and sodium-ion batteries. [Display omitted] Transition metal oxides have been extensively studied due to their large theoretical capacities, but their practical application has been hampered by low electrical conductivity and dramatic volume fluctuation during cycling. In this work, we synthesized Zn 3 V 2 O 8 material using Zn-V-MOF (metal–organic framework) as a sacrificial template to improve the electrochemical characteristics of lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). Unique dodecahedral structure, larger specific surface area and higher ability to mitigate volume changes, improve the electrochemical reaction active site while accelerating ion transport. Zn 3 V 2 O 8 with 2-methylimidazole as a ligand demonstrated a discharge capacity of 1225.9 mAh/g in LIBs and 761.6 mAh/g in SIBs after 300 cycles at 0.2 C. Density functional theory (DFT) calculation illustrates the smaller diffusion barrier energy and higher specific capacity in LIBs that is ascribed to the fact that Li has a smaller size and hence its diffusion is easier. This study may lead to a path for the manufacturing of high-performance LIBs and SIBs. [ABSTRACT FROM AUTHOR]

The potential of MOF-based composites as modifying materials for high-performance lithium‑sulfur battery separators was verified. Therefore, we compounded Ni/Co-PBAs with KB to obtain the PBAs/KB structure and then prepared Ni/Co/KB composites by a carbonization process as a modified layer of the barrier for Li-S Batteries to alleviate the shuttle problem. The specific capacity of the Ni/Co/KB composite decorated separator was 998.6 mAh/g at 0.5C with a coulombic efficiency close to 100%. [Display omitted] Lithium‑sulfur batteries (LSBs) are gradually replacing conventional lithium-ion batteries (LIBs), credited to their high theoretical capacity, low cost, and non-toxicity. Nevertheless, the substantial capacity degradation caused by the polysulfide shuttling during charging and discharging has seriously hindered the commercialization of LSBs. Separator modification with functionalized carbon materials has been found to catalyze the breakdown of polysulfides, thereby improving the efficiency of LSBs. Herein, we synthesized Ni/Co-PBAs with KB structures to subsequently derive Ni/Co/KB composites by a carbonization process, which were later used as a modifier layer on the barrier in LSBs in order to effectively alleviate the shuttle problem. The capacity of the Ni/Co/KB composite decorated separator is found to be 1032 mAh/g at 0.5 C with a coulombic efficiency closer to 100%. In the long-term cycling capability evaluation, the initial cycle is approximately 802.9 mAh/g at 1 C, while capacity retention after 400 cycles is also 678.8 mAh/g, with a high-capacity retention rate of 84.5%. The potential of these composites as modifying materials for superior LSBs separators is verified by experimental and theoretical methods. [ABSTRACT FROM AUTHOR]

Silicon (Si) is regarded as the promising next-generation commercial anode in high energy lithium-ion batteries (LIBs), attributed to its natural abundance, high theoretical capacity (4200 mAh g−1) and low voltage profile (<0.5 V). However, the huge volume change and tremendous capacity fading of silicon during lithiation/de-lithiation have been hindering its practical application. Herein, a facile and scalable method was proposed to prepare the Si nanosheets limited in 3D porous N-doped carbon micro cages (Si@NCM) particles with ternary oxygen-bridged covalent chemical bond, i.e. , Si–O–C bonding. As a kind of anode materials, the Si@NCM rendered an extremely surprising reversible capacity of 930.2 mAh g−1 after 2000 cycles at a current density of 5 A g−1 at ambient temperature. More interestingly, it afforded an overwhelming capacity of 950.7 mAh g−1 after 3000 cycles at 20 A g−1 at 80 °C, with 89.8% capacity retention, and an excellent rate capability of 594.8 mAh g−1 at 50 A g−1. The impressive electrochemical performance was ascribed to its multi-scaled network structure and moderate covalent bonding, which enhanced Li+ diffusion kinetics and accommodated the volume expansion of the silicon. This simple fabrication approach holds great commercial possibility in practical application of next-generation advanced LIBs. • 3D porous Si@C electrodes are prepared by a facial and scalable spray-drying process. • The N-doped carbon shell is propitious to the caption and transportation of Li+. • Formation of Si–O–C and mesopores contributed to the stable operation of Si@NCM. • 3D Si@NCM electrodes exhibited 930.2 mAh·g−1 over 2000 cycles at 5 A g−1. [ABSTRACT FROM AUTHOR]

Traditional manganese trioxide (Mn 2 O 3) as anode materials can be applied to lithium-ion batteries (LIBs), where it possesses excellent electrochemical performance. However, the inherent disadvantages of volume change and poor cycling stability during charge/discharge process hinder the application of transition metal oxide (TMO) in LIBs. Herein, we propose a method to derive Mn 2 O 3 from metal-organic framework in order to mitigate volume change and enhance cycling stability, by virtue of the introduction of oxygen vacancies (O V) and stable template-derived structure for boosted lithium storage properties. Interestingly, M-BTEC (pyromellitic acid based MOF) -derived Mn 2 O 3 represented higher specific capacity of 1227.1 mAh g−1 until 200 cycles with the current density of 0.1 A g−1 while M-IN (isonicotinic acid based MOF) shows 723.4 mAh g−1 with exceptional cycling stability. [Display omitted] • Two different ligands were used to synthesized Mn 2 O 3 and both of which possess cyclic stability and unique structure. • Oxygen vacancies was conducive to boost lithium ion storage performance. • M-BTEC and M-IN displays excellent capacity of 1227.1 mAh g−1while M-IN shows 723.4 mAh g−1 (200 cycles at 0.1 A g−1) [ABSTRACT FROM AUTHOR]

Conventional commercial lithium-ion battery (LIBs) anode materials are being proven hard to meet the demands of the modern advanced energy market due to their disadvantages, such as limited rate capability and theoretical capacity. Elaborate design of novel anode materials with higher energy storage properties has become a major focus of research recently. In this work, a N-doped carbon ZnO/Co 3 ZnC (named as ZnO/Co 3 ZnC) composite is facilely fabricated employing metal-organic framework (MOF) as a sacrificial template. In addition to the formation of N-doped carbon frameworks, the introduction of oxygen vacancies (O V) as well as the unique and stable structure are also conducive to boosting lithium storage properties. As expected, the ZnO/Co 3 ZnC based anode for LIBs displayed remarkable lithium storage properties, such as the specific capacity as high as 1162.4 mAh g−1 (after 300 cycles under 0.2 A g−1) and excellent high-rate performance (~ 533.8 and 473.3 mAh g−1 under 0.5 and 1 A g−1, respectively.) Consequently, this study reinforces the beneficial role of above-mentioned characteristics to render ZnO/Co 3 ZnC an appealing anode material for LIBs. [Display omitted] • N-doped carbon ZnO/Co 3 ZnC composite is fabricated via bimetallic metal-organic framework. • N-doped frameworks and oxygen vacancies were beneficial to boosting lithium storage. • ZnO/Co 3 ZnC displays an excellent capacity of 1162.4 mAh g−1 (300 cycles, 0.2 A g−1). [ABSTRACT FROM AUTHOR]