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Hard carbon serves as a highly promising anode material for sodium‐ion batteries due to its stable structure and cost‐effectiveness. Although the hard template method is commonly employed to enhance the sodium storage capacity, the reported process steps are complicated. In this study, we introduced a facile approach by utilizing ZnO as a self‐sacrificed template to engineer pore structures with one step for template removal without using harmful chemicals. Our investigations reveal that pretreatment of the material before carbonization can reduce the specific surface area and defect degree of the final hard carbon. When utilized as an anode material, the as‐prepared hard carbon demonstrated a reversible capacity of 334 mAh g−1 at 0.05 A g−1 with an initial Coulombic efficiency of 84 %. Even at a high current density of 2 A g−1, the capacity stabilized at 183 mAh g−1 after 1000 continuous cycles. Electrochemical storage behavior and ex‐situ Raman spectroscopy unveiled insights into the potential sodium storage mechanism. These findings present a new approach to enhancing the reversible properties of hard carbon anode materials for high‐performance sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

Potassium‐ion batteries hold practical potential for large‐scale energy storage owing to their appealing cell voltage and cost‐effective features. The development of anode materials with high rate capability and satisfactory cycle lifespan, however, is one of the key elements for exploiting this electrochemical energy storage system at practical levels. Here, a template‐assisted strategy is reported for acquiring a bimetallic telluride heterostructure which is supported on N‐doped carbon shell (ZnTe/CoTe2@NC) that promotes diffusion of K+ ions for rapid charge transfer. It is shown that in telluride heterojunctions, electron‐rich Te sites and built‐in electric fields contributed by electron transfer from ZnTe to CoTe2 concomitantly provide abundant cation adsorption sites and facilitate interfacial electron transport during potassiation/depotassiation. The relatively fine ZnTe/CoTe2 nanoparticles imparted by the heterojunction result in high structural stability, together with a highly reversible capacity up to 5000 cycles at 5 A g−1. Moreover, using judiciously combined experiment and theoretical computation, it is demonstrated that the energy barrier for K+ diffusion in telluride heterojunctions is significantly lower than that in individual counterparts. This quantitative design for fast and durable charge transfer in telluride heterostructures can be of immediate benefit for the rational design of batteries for low‐cost energy storage and conversion. [ABSTRACT FROM AUTHOR]

Nonuniform local electric field and few nucleation sites on the reactive interface tend to cause detrimental lithium (Li) dendrites, which incur severe safety hazards and hamper the practical application of Li metal anodes in batteries. Herein, a carbon nanofiber (CNF) mat decorated with ultrafine titanium nitride (TiN) nanoparticles (CNF‐TiN) as both current collector and host material is reported for Li metal anodes. Uniform Li deposition is achieved by a synergetic effect of lithiophilic TiN and 3D CNF configuration with a highly conductive network. Theoretical calculations reveal that Li prefers to be adsorbed onto the TiN sheath with a low diffusion energy barrier, leading to controllable nucleation sites and dendrite‐free Li deposits. Moreover, the pseudocapacitive behavior of TiN identified through kinetics analysis is favorable for ultrafast Li+ storage and the charge transfer process, especially under a high plating/stripping rate. The CNF‐TiN‐modified Li anodes deliver lower nucleation overpotential for Li plating and superior electrochemical performance under a large current density (200 cycles at 3 mA cm−2) and high capacity (100 cycles with 6 mAh cm−2), as well as a long‐running lifespan (>600 h). The CNF‐TiN‐based full cells using lithium iron phosphate and sulfur cathodes exhibit excellent cycling stability. [ABSTRACT FROM AUTHOR]

Abstract: Well dispersed MnCO3/carboxylated carbon nanotube (CNT) nanocomposites are prepared by a facile solution precipitation method. Transmission electron microscopy (TEM) characterizations show that due to heterogeneous nucleation sizes the addition of carboxylated CNT is able to suppress growth of MnCO3 particles, resulting in formation of nano-sized particles. Electrochemical characterization of lithiation/delithiation of the MnCO3/CNT nanocomposites reveals a large capacity of 772mAhg−1 for the first cycle with 84% capacity retention after 100 cycles. The superior electrochemical performance of the MnCO3/CNT nanocomposites electrode compared to the pure MnCO3 electrode can be attributed to super-fine particles and good conductivity due to the presence of CNTs. Their large surface area facilitates fast lithium ion and electron transport and accommodates the big volume change during the conversion reactions. [Copyright &y& Elsevier]