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Comprehensive Summary: Rationally developing efficient and durable bifunctional catalysts toward oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is critical for rechargeable zinc‐air batteries (ZABs). Herein, a bead‐like CoSe2@NC@NCNFs bifunctional catalyst was designed and fabricated by confining cubic CoSe2 nanoparticles to three‐dimensional (3D) porous MOFs‐derived nitrogen‐doped carbon (NC) and one‐dimensional (1D) N‐doped carbon nanofibers (NCNFs) through a facile encapsulate strategy. The 1D/3D continuous network structure contributes to the improvement of specific surface area and electronic conductivity, while the strong synergistic effect between CoSe2 sites and Co‐Nx‐C sites can effectively enhance electron/mass transfer and reduce the diffusion resistance. The as‐constructed CoSe2@NC@NCNFs catalyst exhibits high catalytic activity and stability toward ORR/OER with a high half‐wave potential of 0.80 V (vs. RHE) in ORR and a low overpotential of 280 mV at 10 mA·cm−2 in OER. More encouragingly, the rechargeable ZABs with CoSe2@NC@NCNFs cathode deliver high peak power densities (126.8 mW·cm−2), large specific capacities (763.1 mA·h·g−1), and robust charge‐discharge cycling stability over 240 cycles. This study provides a facile strategy for designing efficient bifunctional catalysts for rechargeable energy conversion applications. [ABSTRACT FROM AUTHOR]

Captured by the remarkable environmental/economic value, recycling spent LiFePO4 has attracted numerous attention. However, restricted by diverse failure mechanisms and different particle‐sizes/active‐sites, recycling strategies still suffer from uneven repairing results and poor accessibility. For promoting their application in commercial systems, the uniform physical‐chemical properties are urgent for regenerated samples. Herein, by tailoring oxidation‐reduction manners, the homogeneous cathode materials can be prepared, displaying uniform particle size and restored lattice. The capacity of as‐optimized samples can be kept ≈141.5 mAh g−1 at 1.0 C, and 137 mAh g−1 with a retention of 92% after 300 cycles at 2.0 C. After Kg‐scale experiments, the pouch full‐cell (LFP‐500 vs recovered graphite) delivers ≈4200 mAh capacity, with considerable cycling stability (retention 96.83%, after 500 loops). Importantly, the detailed mechanism of oxidation/reduction‐conditions is investigated, especially their lattice reconstitution and ions‐ diffusion behaviors. Supported by kinetic analysis and DFT calculations, the fascinating stability of LFP‐500 is further proved, mainly derived from the accelerated Li‐diffusion behaviors. Compared to traditional recovering manners, oxidation/reduction process displays low cost, energy‐consumption, and pollution, accompanied with considerable large‐scale application potential. Given this, this work is anticipated to illustrate the in‐depth mechanism of lattice‐reconstruction, while offering significant strategies for large‐scale and homogenized regeneration. [ABSTRACT FROM AUTHOR]

Hard carbon (HC) is widely regarded as the most promising anode material for sodium‐ion batteries (SIBs). For improving the sodium storage capacity of HC anode, current research primarily focuses on the high‐voltage slope region. Actually, increasing the storage capability in the low‐voltage plateau region is more important for enhancing the energy density of full cells. Therefore, in this study, HC anode with rich closed pore structure is designed and constructed with the help of carbon dots (CDs), and it is demonstrated that the presence of closed pore structure can provide more sodium storage sites in the plateau region, resulting in an obvious increase of sodium storage capacity. Moreover, the pore‐filling and intercalation mechanism for sodium storage in plateau region is revealed by in situ Raman spectroscopy and ex situ transmission electron microscopy (TEM). It is worth noting that the increase in capacity induced by closed pore‐filling is not accompanied by a decrease in initial coulombic efficiency (ICE), due to the fact that the introduction of closed pores does not increase the contact area between electrode and electrolyte. This work presents novel concepts for the structural design of HC and provides valuable insights into the effective utilization of plateau region in SIBs. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) have rapidly risen to the forefront of energy storage systems as a promising supplementary for Lithium‐ion batteries (LIBs). Na3V2(PO4)2F3 (NVPF) as a common cathode of SIBs, features the merits of high operating voltage, small volume change and favorable specific energy density. However, it suffers from poor cycling stability and rate performance induced by its low intrinsic conductivity. Herein, we propose an ingenious strategy targeting superior SIBs through cross‐linked NVPF with multi‐dimensional nanocarbon frameworks composed of amorphous carbon and carbon nanotubes (NVPF@C@CNTs). This rational design ensures favorable particle size for shortened sodium ion transmission pathway as well as improved electronic transfer network, thus leading to enhanced charge transfer kinetics and superior cycling stability. Benefited from this unique structure, significantly improved electrochemical properties are obtained, including high specific capacity (126.9 mAh g−1 at 1 C, 1 C = 128 mA g−1) and remarkably improved long‐term cycling stability with 93.9% capacity retention after 1000 cycles at 20 C. The energy density of 286.8 Wh kg−1 can be reached for full cells with hard carbon as anode (NVPF@C@CNTs//HC). Additionally, the electrochemical performance of the full cell at high temperature is also investigated (95.3 mAh g−1 after 100 cycles at 1 C at 50 °C). Such nanoscale dual‐carbon networks engineering and thorough discussion of ion diffusion kinetics might make contributions to accelerating the process of phosphate cathodes in SIBs for large‐scale energy storages. [ABSTRACT FROM AUTHOR]

Further commercialization of Ni‐rich layered cathodes is hindered by severe structure/interface degradation and kinetic hindrance that occur during electrochemical operation, which leads to safety risks and reduced range in electric vehicles (EVs). Herein, by selecting elements with different solubility properties, a multifunctional strategy that synchronously fabricates perovskite‐type SrZrO3 coating and Sr/Zr co‐doping is employed to strengthen the structure/interface stability and the Li+ transport mobility of LiNi0.85Co0.10Mn0.05O2 (NCM). Perovskite‐type SrZrO3 protective layers formed on the particle surface can substantially mitigate the unexpected interfacial side reactions and surface phase transitions. In addition, a robust crystal framework is constructed by optimizing local O coordination through the introduction of strong Zr−O bonds. Notably, Li+ diffusion kinetics is effectively improved due to expanded cell parameters and O‐Li‐O slab spacing with the incorporation of large‐diameter Sr pillar ions, as revealed by X‐ray diffraction. As a result, the Sr/Zr‐modified NCM achieves a remarkable capacity retention of 99.4% after 200 cycles at 1 C, and a high rate capacity of 168.9 mAh g−1 at 10 C. This work opens new avenues to develop high‐performance NCM cathodes with high energy and high power for EVs with long calendar life. [ABSTRACT FROM AUTHOR]

Titanium oxides have been considered promising anode materials for lithium-ion batteries (LIBs). However, the poor conductivity and low specific capacity of bulk titanium oxides limit their application. In this study, a carbon dot-modified TiO2@SiO2 aerogel was successfully fabricated through a facile ambient pressure drying strategy and used as an anode material of LIBs. Benefiting from the crosslinking of carbon dots and the surface modification of SiO2, the as-prepared hierarchical aerogel exhibited a high initial discharge capacity of 974 mAh g−1 and maintained a capacity of 299 mAh g−1 after 100 cycles at 0.1 A g−1. It also retained a discharge capacity of 111 mAh g−1 with a CE of 99.9% at 3 A g−1. The carbon dot-modified cross-linking skeleton contributes to the structural integrity of the TiO2@SiO2 aerogel during repeated insertion/extraction of lithium ions, guaranteeing outstanding cycling and high-rate performance. This ambient pressure drying strategy provides a facile and feasible way to produce high-performance aerogel anode materials for lithium-ion storage.Highlights: Carbon dots-modified TiO2@SiO2 aerogel was fabricated via ambient pressure drying. The hierarchical aerogel shows high initial discharge capacity of 974 mAh g−1. TiO2@SiO2 aerogel exhibits structural integrity and outstanding cycling performance. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have been proposed as novel fillers for constructing polymer solid electrolytes based composite electrolytes. However, MOFs are generally used as passive fillers, in‐depth revealing the binding mode between MOFs and polyethylene oxide (PEO), the critical role of MOFs in facilitating Li+ transport in solid electrolytes is full of challenges. Herein, inspired by density functional theory (DFT) the 2D‐MOF with rich unsaturated metal coordination sites that can bind the O atom in PEO through the metal–oxygen bond, anchor TFSI− to release Li+, resulting in a remarkable Li+ transference number of 0.58, is reported according well with the experimental results and molecular dynamics (MD) simulation. Impressively, after the introduction of the 2D‐MOF, the Li+ can rapidly hop along the benzene ring center within the 2D‐MOF plane, and the interface between the benzene ring and PEO can also serve as a fast Li+ migration pathway, delivering multiple ion‐transport channels, which present a high ion conductivity of 4.6 × 10−5 S cm−1 (25 °C). The lithium symmetric battery is stable for 1300 h at 60 °C, 0.1 mA cm−2. The assembled lithium metal solid state battery maintains high capacity of 162.8 mAh g−1 after 500 cycles at 60 °C and 0.5 C. This multiple ion‐transport channels approach brings new ideas for designing advanced solid electrolytes. [ABSTRACT FROM AUTHOR]