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The cost‐efficient ZnMnO3 has attracted increasing attention as a prospective anode candidate for advanced lithium‐ion batteries (LIBs) owing to its resourceful abundance, large lithium storage capacity and low operating voltage. However, its practical application is still seriously limited by the modest cycling and rate performances. Herein, a facile design to scalable synthesize unique one‐dimensional (1D) mesoporous ZnMnO3 nanorods (ZMO‐NRs) composed of nanoscale particles (≈11 nm) is reported. The 1D mesoporous structure and nanoscale building blocks of the ZMO‐NRs effectively promote the transport of ions/electrons, accommodate severe volume changes, and expose more active sites for lithium storage. Benefiting from these appealing structural merits, the obtained ZMO‐NRs anode exhibits excellent rate behavior (≈454 mAh g−1 at 2 A g−1) and ultra‐long term cyclic performance (≈949.7 mAh g−1 even over 500 cycles at 0.5 A g−1) for efficient lithium storage. Additionally, the LiNi0.8Co0.1Mn0.1O2//ZMO‐NRs full cell presents a practical energy density (≈192.2 Wh kg−1) and impressive cyclability with approximately 91 % capacity retention over 110 cycles. This highlights that the ZMO‐NRs product is a highly promising high‐rate and stable electrode candidate towards advanced LIBs in electronic devices and sustainable energy storage applications. [ABSTRACT FROM AUTHOR]

To optimize the cycle life and rate performance of lithium‐ion batteries (LIBs), ultra‐fine Fe2O3 nanowires with a diameter of approximately 2 nm uniformly anchored on a cross‐linked graphene ribbon network are fabricated. The unique three‐dimensional structure can effectively improve the electrical conductivity and facilitate ion diffusion, especially cross‐plane diffusion. Moreover, Fe2O3 nanowires on graphene ribbons (Fe2O3/GR) are easily accessible for lithium ions compared with the traditional graphene sheets (Fe2O3/GS). In addition, the well‐developed elastic network can not only undergo the drastic volume expansion during repetitive cycling, but also protect the bulk electrode from further pulverization. As a result, the Fe2O3/GR hybrid exhibits high rate and long cycle life Li storage performance (632 mAh g−1 at 5 A g−1, and 471 mAh g−1 capacity maintained even after 3000 cycles). Especially at high mass loading (≈4 mg cm−2), the Fe2O3/GR can still deliver higher reversible capacity (223 mAh g−1 even at 2 A g−1) compared with the Fe2O3/GS (37 mAh g−1) for LIBs. Winning ribbon: Graphene ribbon networks can effectively improve electron/ion transfer to enhance the battery performance of hybrids, especially at high mass loading. Ultra‐fine Fe2O3 nanowires uniformly anchored on interconnected graphene ribbon networks are successfully synthesized, and exhibit high rate and long cycle life performance. [ABSTRACT FROM AUTHOR]

Abstract Developing high volumetric capacity and long cycle-life anode materials for high-performance lithium-ion batteries (LIBs) still remains a great challenge. Herein, densely pillared holey-graphene block with high N-doping (P-NHG) has been successfully synthesized through thermal decomposition of (NH 4) 6 Mo 7 O 24 in-between stacked GO sheets. The dense graphene building block processes a high packing density of 2.53 g cm−3, high nitrogen doping (19.2 at%), numerous holes on the graphene sheet, and ∼5 nm Mo 2 C nanoparticles as the pillars in-between the graphene sheets, facilitating rapid ion diffusion and storage and ensuring structural stability during Li ion storage. As a result, the P-NHG electrode can deliver high gravimetric capacity of 1221 mAh g−1 and ultrahigh volumetric capacity of 3089 mAh cm−3 at 0.1 A g−1, as well as excellent cyclability (713 mAh g−1/1803 mAh cm−3 after 300 cycles at 0.5 A g−1). The novel design of densely pillared holey-structure materials represents greatly improved properties such as superior cyclability, and high volumetric capacity for LIBs. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

There are crucial demands for high power density and long-term cycling performance of Li-ion batteries (LIBs), and the development of stable electrode material operating at high current densities still remains a challenge. Here we develop a novel strategy for the synthesis of flexible N-doped carbon nanofiber/CoFe 2 O 4 film (CoFe 2 O 4 @N-CNF) with a double-layer carbon protection by electrospinning, which possesses stable carbon shell and honeycomb-like core with CoFe 2 O 4 nanosheets embedded into conductive and interconnected carbon nanosheets. The unique structure is beneficial for providing robust structural stability upon long-term cycling, and offering nitrogen-rich interconnected mesoporous and conductive carbon matrix for fast charge and ion transport. As a consequence, the optimized CoFe 2 O 4 @N-CNF exhibits a high reversible capacity of 858 mAh g −1 at 0.1 A g −1 , excellent rate capability (306 mAh g −1 at 30 A g −1 ), and superior cycling stability up to 10,000 cycles with almost no capacity loss at 10 A g −1 . We believe that this proposed methodology has a profound impact on drastic improvements of various flexible energy storage devices. [ABSTRACT FROM AUTHOR]

In the work, a facile yet efficient self-sacrifice strategy is smartly developed to scalably fabricate hierarchical mesoporous bi-component-active ZnO/ZnFe2O4 (ZZFO) sub-microcubes (SMCs) by calcination of single-resource Prussian blue analogue of Zn3[Fe(CN)6]2 cubes. The hybrid ZZFO SCMs are homogeneously constructed from well-dispersed nanocrstalline ZnO and ZnFe2O4 (ZFO) subunites at the nanoscale. After selectively etching of ZnO nanodomains from the hybrid, porously assembled ZFO SMCs with integrate architecture are obtained accordingly. When evaluated as anodes for LIBs, both hybrid ZZFO and ZFO samples exhibit appealing electrochemical performance. However, the as-synthesized ZZFO SMCs demonstrate even better electrochemical Li-storage performance, including even larger initial discharge capacity and reversible capacity, higher rate behavior and better cycling performance, particularly at high rates, compared with the single ZFO, which should be attributed to its unique microstructure characteristics and striking synergistic effect between the bi-component-active, well-dispersed ZnO and ZFO nanophases. Of great significance, light is shed upon the insights into the correlation between the electrochemical Li-storage property and the structure/component of the hybrid ZZFO SMCs, thus, it is strongly envisioned that the elegant design concept of the hybrid holds great promise for the efficient synthesis of advanced yet low-cost anodes for next-generation rechargeable Li-ion batteries. [ABSTRACT FROM AUTHOR]

In this work, we rationally designed an efficient template-free synthetic strategy to fabricate hierarchical mesoporous hollow ZnMn2O4 sub-microspheres (HZSMs) constructed entirely from nanoparticle (NP) building blocks of size ≈15 nm. The well-known inside-out Ostwald ripening process was tentatively proposed to shed light on the formation mechanism of the mesoporous hollow nano-/microarchitecture. In favor of the intrinsic structural advantages, these resulting HZSMs exhibited superior electrochemical lithium-storage performance with high specific capacity, excellent cyclability, and good rate capability when evaluated as an anode material for advanced Li-ion batteries (LIBs). The excellent electrochemical performance should be reasonably ascribed to the porous and hollow structure of the unique HZSMs with nanoscale subunits, which reduced the diffusion length for Li+ ions, improved the kinetic process and enhanced the structural integrity with sufficient void space for tolerating the volume variation during the Li+ insertion/extraction. These results further revealed that the as-prepared mesoporous HZSMs would be a promising anode for high-performance LIBs. [ABSTRACT FROM AUTHOR]

The interface between metal oxide and conductive carbon material is important for rate performance and cycling stability of the electrode materials for lithium-ion batteries. Herein, we present a simple strategy for tightly anchoring ultra-small NiO nanoparticles on nitrogen-doped flower-like carbon scaffold through strong Ni–O–C and Ni–C dual chemical bonds. Benefiting from the robust interfacial interaction and high surface compatibility, the overall conductivity and structural robustness of the NiO/Ni/nitrogen-doped carbon complex improve significantly. Moreover, the unique open-porous structure which consists of interconnected carbon sheets provides sufficient electron/ion transport paths. Therefore, the composite reveals high capacity as high as 1025 mAh g−1 at 0.1 A g−1, superior rate capability (468 mAh g−1 at 2 A g−1) and remarkable cyclic stability (662 mAh g−1 retention after 500 cycles at 0.5 A g−1). Image 1 • NiO nanoparticles are anchored on flower-like carbon by Ni–C and Ni–O–C bonds. • Strong interfacial interaction greatly promotes the charge-transfer kinetics. • Open porous carbon networks provide abundant electron and ion transport paths. • The composite exhibits high-rate and good stability for Lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Si has attracted more attention as an ideal anode for next-generation Li-ion batteries (LIBs), due to its large theoretical capacity and low de-lithiation voltage. However, extreme volume change (about 300%) and low electronic conductivity severely hinder its practical application. Herein, to overcome these problems, via the electrospinning and pyrolysis processes, Si nanoparticles are embedded in porous N-doped carbon fibers (Si/P-NCFs) and interwoven into a flexible film. The binder-free and flexible Si/P-NCFs can significantly enhance the Li-ion storage capacity (1386 mAh g−1 after 100 cycles at 0.1 A g–1), cycling stability (942 mAh g−1 over 1000 cycles at 1 A g−1), as well as rate capability (381 mAh g−1 at 10 A g−1). These improvements are ascribed to the spatial confinement of carbon fibers and buffering effect of porous structure, which synergistically prevent the harm caused by the volume change. Additionally, porous N-doped carbon networks and binder-free structure can significantly enhance electron/ion conductivities. This work demonstrates an effective design to address the volume change and low electronic conductivity of Si towards advanced flexible Si-based anodes, as well as exhibits promising potential in practical use. [Display omitted] • Si are embedded in porous N-doped carbon fibers and interwoven into a flexible film. • Confinement of carbon fibers and porous structure can buffer volume change of Si. • Carbon fibers, N-doping, and porous structure can facilitate charges/ions transfer. • The binder-free and flexible Si/P-NCFs exhibits improved Li-ion storage properties. [ABSTRACT FROM AUTHOR]

Sodium ion batteries (SIBs) have been considered as a promising candidate to supersede lithium ion batteries, however, the lack of suitable electrode materials for efficient Na-storage still hinders its practical use. Hence, this work reports a general and effective way to in-situ construction of heterostructured SnSe/SnTe nanodots encapsulated in nitrogen-doped mesoporous carbon matrix (SnSe/SnTe@N-CNFs). In such unique architecture, the porous N-CNFs matrix cannot only provide high electronic/ion conductivity but also alleviate the volume change of SnSe and SnTe, leading to rapid kinetics and robust structure, whereas the ultrasmall SnSe/SnTe heterostructure with built-in interfacial driving force can promote charge transfer kinetics. Meanwhile, the abundant defective sites induced from high-level N-doping is beneficial to Na+ storage. Besides, the formed Sn–C, Se–C, and Te–C bonds can improve the interfacial interaction between SnSe/SnTe and N-CNFs, thus enhancing electronic conductivity, suppressing the aggregation and detachment of active components, and ensuring rapid kinetics and structural integrity. When evaluated as an anode for SIBs, the as-prepared SnSe/SnTe@N-CNFs exhibits high reversible capacity, remarkable cycling stability, and superior rate capability. This work can offer an efficient and universal strategy for designing advanced anode materials with exceptional performance. [Display omitted] • Highly conductive and porous N-CNFs matrix alleviates the volume change of SnSe/SnTe. • Strong chemical bonds between SnSe/SnTe and N-CNFs improve interfacial interaction. • High-level N-doping affords abundant defective sites for Na+ storage. • Storage mechanism and kinetics of Na+ in SnSe/SnTe@N-CNFs anode is revealed. • SnSe/SnTe@N-CNFs heterostructure exhibits superior electrochemical performance. [ABSTRACT FROM AUTHOR]

As an anode material for lithium ion batteries (LIBs), Bi 2 S 3 possesses high redox activity and theoretical capacity. However, severe volume variation (alloying/dealloying processes) and active sulfide loss (dissolution of polysulfides) during cycling always result in rapid capacity degradation. Thus, we fabricated MOF-derived Bi 2 S 3 hybrid nanofibers coated by organic framework via facile polymerization and sulfidation processes. Such unique coating nanolayers derived from the cross-linked organic framework based on the Bi-MOF (CAU-17) can effectively tolerate the volume expansion and active sulfide loss, thus leading to excellent cycling stability (1059 mAh g−1 at 0.1 A g−1 after 100 cycles, 1108 mAh g−1 at 1.0 A g−1 after 500 cycles), and rate performance (478 mAh g−1 at 10 A g−1). This study offers a hopeful anode for highly efficient Li-ion storage, and a simple and low-energy-consuming strategy to improve the electrochemical performance of active materials. [Display omitted] • MOF-derived Bi 2 S 3 was prepared by a simple sulfidation process. • Bi-MOF-derived coating layer can effectively tolerate the active sulfide loss. • The MOF-derived Bi 2 S 3 hybrid showed an excellent reversible capacity. [ABSTRACT FROM AUTHOR]