Jian Wang

Layered CrSe2 reversibly accommodates approximately one potassium (K) per formula unit, but the structural origin of its rate-dependent capacity remains unresolved. Operando synchrotron X-ray diffraction (SXRD) reveals the sequential P-3m1-R3m-C2/m phase pathway during cycling at different current rates. The P-3m1/R3m transformation exhibits the lattice discontinuity and becomes incomplete when increasing the current rate, as directly observed by operando SXRD. Chemical K deintercalation and state-resolved impedance measurements provide complementary evidence for sluggish kinetics near the fully deintercalated regime. Restricting the upper cutoff voltage will sacrifice some capacity but will improve electrochemical cycling capacity retention. These findings identify a particularly rate-sensitive structural region and show how phase-resolved characterization can guide voltage-window selection for layered potassium-storage electrodes.

Dissatisfactory electrochemical performance of wide‐temperature lithium‐sulfur batteries (LSBs) originates from the sluggish Li ⁺ desolvation and successive sulfur specie conversion kinetics at the interface and within the cathode interior. Herein, different from electrolyte engineering, a self‐tandem catalysis enabled cascade reactions is developed to drive Li ⁺ kinetics and associated polysulfide conversions in wide‐temperature LSBs. By incorporating electron‐adjustable atom‐level Ce as the self‐tandem catalyst onto defect‐rich Co, Fe‐based layered double hydroxides (EAAC@D‐LDH), a favorable solvation microenvironment is established to decrease the related barriers toward promoting rapid Li ⁺ desolvation, sulfur conversion, and Li ₂ S delithiation kinetics, as revealed in Raman analysis, electrochemical evaluations, and ex‐situ interfacial morphology as well as composition characterization. Such improved reaction kinetics enable the sulfur cathodes work well in a wide temperature ranging from 0 to ‐30°C, and it retains high‐capacity retention of 94% at 5C. Under ‐20°C, the cells remain the capacity of 85% at 0.1C, respectively. Remarkably, a stable capacity is reserved even at an ultralow temperature of ‐30°C, demonstrating that the substantial promise of this self‐tandem catalysis supports cascade reaction refinement strategy toward high performance wide‐temperature LSBs.

The shuttling effect and sluggish conversion kinetics of lithium polysulfides (LiPSs) hinder the further advancement of lithium‐sulfur (Li‐S) batteries, exhibiting high barriers. Among catalysts, single‐atom catalysts (SACs) can accelerate LiPSs redox kinetics by leveraging M‐S coordination, interfacial charge transfer, and anchoring effect of coordinating heteroatoms. Numerous researches have reported improved catalytic activity via screening central metal and coordinating atoms as well as optimizing coordination configurations. However, systematic summary concerning the principles in screening and design of asymmetric coordination structures, the evolution mechanisms of orbital hybridization and spatial geometry, and the corresponding structure‐activity relationships governing LiPSs conversion kinetics remain unknown. In this review, we systematically summarize the modifications brought by asymmetric coordination chemistry and dual‐atom coordination structures in terms of geometric configuration engineering, molecular orbital hybridization, and interfacial charge rearrangement, together with the underlying mechanisms for boosting LiPSs conversion kinetics. Centered on theoretical calculations supplemented by experimental validations, we elaborate the critical significance of asymmetric coordination chemistry of SACs in elevating the catalytic efficiency. Finally, the future developments of SACs in Li─S batteries are outlooked and prospected.

The slow kinetics of sulfur cathodes caused by the high energy barriers of Li ⁺ desolvation stem primarily from the structure of the inner Helmholtz plane (IHP). Herein, a synergistic strategy combining electrochemical tandem catalysis with spatial nanoconfinement is proposed to regulate the Li(solvent) _x ⁺ dynamics. As a proof-of-concept, the porous covalent organic framework (denoted as TPBD) decorated MXene is in situ constructed, acting as a tandem kinetic promoter. The theoretical simulations and in situ Raman reveal that the porous TPBD layer confines the bulky Li(solvent) _x ⁺ species and sieves the spatial structure with accelerated Li ⁺ diffusion kinetics. Meanwhile, MXene serves as a negatively charged substrate that helps disrupt anion-solvent interactions and reconstruct the solvation structure at the IHP, thereby enhancing Li ⁺ kinetics and sulfur redox reversibility. Encouragingly, the assembled cells demonstrate a superior Li ⁺ transference number (0.77), long-term cycling lifespan up to 1000 cycles, as well as excellent areal capacity (>6 mAh cm ⁻² ) at 0°C and superior rate capability at 50°C under a high sulfur loading of 7.51 mg cm ⁻² . The as-prepared pouch cell remains stable for over 100 cycles, validating this novel integration of catalysis and nanoconfinement for tandem kinetics in Li-S batteries.

Aqueous zinc metal batteries are promising for safe and low-cost energy storages, but their practical operation is limited by unstable Zn/electrolyte interfacial reactions, sluggish Zn2+ transport, parasitic hydrogen evolution reaction (HER), and dendritic growth. Here, we report a strategy of constructing a dual-functional rapidly ion-accelerated versatile electron-regulating interphase on Zn metal anode (DRIVE@Zn) through a room-temperature immersion co-deposition process. Specifically, the Ag/Bi-derived DRIVE interphase regulates Zn2+ pathway, facilitates desolvation, homogenizes Zn2+ flux, and guides Zn deposition at the interface rather than on random exposed surface defects, which are verified by simulations and in situ electrochemical analyses. Consequently, DRIVE@Zn delivers an average Coulombic efficiency of 99.65%, stable Zn∥Zn cycling for over 3100 h at 5 mA cm–2, and durable Zn∥I2 full-cell lifespan for 25,000 cycles at 5 A g–1. This work highlights interphase-regulated Zn2+ pathway as an effective route toward long-cycling aqueous Zn metal anodes.

Aqueous zinc-ion batteries (AZIBs) offer a safe, scalable path to grid storage, but their progress is limited by cathode materials that exhibit sluggish Zn2+ diffusion. Commercial vanadium pentoxide (V2O5), though possessing a high theoretical capacity, inherently suffers from this kinetic limitation. Here, a water-assisted mechanochemical strategy is developed to introduce interlayer hydration and V4+-rich oxygen defects into commercial V2O5, improving both ion transport and electron transfer. Hydration expands the interlayer spacing for Zn2+ migration, while V4+ states enhance charge transfer, forming a coupled ion–electron pathway. The treatment also expands the (001) spacing, creates oxygen vacancies, and exfoliates bulk particles into porous nanosheets. The optimally modified V2O5 cathode delivers exceptional Zn2+ storage performance with a high reversible capacity of 563.7 mAh g–1 at 0.2 A g–1, outstanding cycling stability with 237 mAh g–1 retained after 5000 cycles at 10 A g–1, and a near-unity Coulombic efficiency. Comprehensive kinetic analyses confirm that the modified V2O5 exhibits a dominant pseudocapacitive mechanism, significantly reduced charge-transfer resistance, and an order-of-magnitude enhancement in the apparent Zn2+ diffusion coefficient. This work demonstrates that the coordinated regulation of interlayer water and oxygen vacancies is a highly effective strategy to activate commercial V2O5, and the mechanochemical route provides a potentially scalable strategy for activating commercial oxide cathode materials.

Gel polymer electrolytes (GPEs) rich in ether oxygen side chains have attracted particular interests in high‑energy‑density lithium metal batteries (LMBs). However, the strong coordination between their polymer framework and lithium ions (Li ⁺ ) leads to a high desolvation energy barrier at low temperatures. Herein, by comparing the side‑chain electronic effects, this work constructs an ether‐oxygen‐based gel polymer electrolyte (E‐GPE) with electron‐donating ether oxygen side chains and a fluorinated GPE (F‐GPE) with electron‐withdrawing trifluoromethyl side chains, with N,N‐dimethyl trifluoroacetamide (FDMA) as a low‐temperature additive. Density functional theory (DFT) calculations reveal that the electron‐donating side chains in E‐GPE enhance the binding energy between the polymer framework and Li ⁺ , thereby impeding Li ⁺ desolvation. Conversely, the electron‐withdrawing side chains in F‐GPE weaken the binding energy between the polymer framework and Li ⁺ , lowering the Li ⁺ desolvation barrier and inducing the formation of LiF‐rich interphase. Consequently, Li/F‐GPE/Li cells stably cycle for over 1000 h at −20°C, and Li/F‐GPE/LiCoO ₂ coin cells retain 88.7% of their original capacity after 400 cycles at −20°C. Furthermore, pouch cells steadily power a light‐emitting diode (LED) after shear damage, demonstrating potential safety. This work provides a new design paradigm for developing GPEs for high‐energy‐density LMBs in extreme environments.

An anion-dominated localized high-concentration quasi-solid-state electrolyte induces uniform LiF-rich CEI. This stable interface leads to stable battery cycling.