Sai Che

Lithium‐sulfur batteries (LSBs) have attracted extensive attention owing to their high energy density. However, their development remains severely hindered by sluggish interfacial reaction kinetics, unstable electrode–electrolyte interphases, lithium dendrite growth, and polysulfide shuttling. In this work, we identify a hidden quasi‐chelation effect in ether‐based nitrile solvents, which undermines the effectiveness of weakly solvating electrolyte design, and demonstrate that this limitation can be effectively overcome through a thioether‐substitution strategy. Specifically, replacing the ether oxygen in methoxyacetonitrile with sulfur to form (methylthio)acetonitrile disrupts the quasi‐chelating coordination motif and weakens solvent‐Li ⁺ interactions, and induces anion‐rich solvation structures. Spectroscopic characterizations combined with molecular dynamics simulations reveal that breaking this quasi‐chelation effect lowers the Li ⁺ desolvation barrier and accelerates ion‐transport kinetics. Meanwhile, the preferential decomposition of the thioether solvent promotes the formation of sulfur‐rich, inorganic‐dominated interphases, thereby enabling simultaneous stabilization of both the lithium metal anode and the SPAN cathode. As a result, lithium dendrite growth and polysulfide shuttling are effectively suppressed, and Li||SPAN full cells retain 86% of their initial capacity after 600 cycles under high‐loading conditions. This work demonstrates that quasi‐chelation breaking can serve as an effective molecular design principle for constructing weakly solvating electrolytes toward practical lithium‐sulfur batteries.

Solid-state polymer electrolytes are considered promising alternatives to conventional liquid electrolytes for improving the safety and energy density of lithium batteries. However, their practical application is still limited by insufficient room-temperature ionic conductivity, low lithium-ion transference number, poor mechanical robustness, and unstable electrode/electrolyte interfaces. Ionic covalent organic frameworks (iCOFs), as charged and crystalline porous polymers, provide a unique platform for regulating ion transport and interfacial behavior through ordered channels, tunable ionic sites, and designable framework structures. In this review, recent progress in iCOF-based solid-state polymer electrolytes is summarized from a charge–structure–function perspective. First, representative synthetic strategies for iCOFs are discussed, including direct synthesis and postmodification, with emphasis on how ionic-site distribution, crystallinity, pore accessibility, and membrane processability influence electrolyte performance. Subsequently, the applications of cationic, anionic, and zwitterionic COFs in solid-state electrolytes are reviewed. Cationic COFs mainly promote lithium-salt dissociation and anion immobilization. Anionic COFs enable quasi-single-ion or single-ion conduction. Zwitterionic COFs provide dual-charge regulation for Li+ transport and interfacial stabilization. The structure–performance relationships of representative iCOF-based electrolytes are critically compared in terms of ionic conductivity, lithium-ion transference number, electrolyte architecture, and battery performance. Finally, the remaining challenges and future opportunities are discussed, including the construction of continuous ion-transport pathways, improvement of polymer–COF compatibility, scalable membrane fabrication, standardized electrochemical evaluation, and clarification of intrinsic ion-conduction mechanisms. This review highlights the potential of iCOFs as functional ion-transport frameworks for safer and higher-performance solid-state lithium batteries.

Lithium metal batteries (LMBs) are promising candidates for high‐energy‐density energy storage systems. However, their practical applications are severely hindered by interfacial instability and uncontrolled lithium deposition, which lead to dendrite growth, low Coulombic efficiency, and rapid capacity decay. In this review, we systematically analyze interfacial processes in LMBs with non‐aqueous liquid electrolytes from a process‐oriented perspective. We employ a six‐step kinetic framework involving ion transport, desolvation, interphase transport, charge transfer, nucleation, and morphological evolution. We first discuss the fundamental structure and dynamic evolution of electrode‐electrolyte interphases, followed by an overview of advanced characterization techniques across multiple length and time scales. Furthermore, recent strategies for regulating interfacial stability are critically summarized, including electrolyte additives, artificial protective layers, and solvation regulation designs. Instead of categorizing these strategies solely by materials, we emphasize their roles in regulating key kinetic steps and clarify the underlying mechanisms within the six‐step process. Finally, we highlight current challenges and future directions toward practical LMBs, including full‐cell and pouch‐cell validation, high energy density, cost reduction, and manufacturing compatibility. This work aims to provide a unified framework for understanding, characterizing, and regulating interfacial stability in lithium metal batteries.

A strategy using an electric field-sensitive solubilizing additive is developed to improve ionic conductivity and interfacial stability for stable lithium metal batteries.

A high-performance NiSe₂–CoSe₂ aerogel was prepared via facile gelation and selenium vapor deposition for efficient water splitting. Its heterostructure and aerogel morphology provided high intrinsic activity and abundant active sites, respectively.

Revealing the underlining interactions between different active sites is of great significance to the rational design of highly efficient non-noble-metal composites for the hydrogen evolution reaction. Herein, we report a pre-chelation assisted one-pot synthesis of a heterostructure CoSe/Co–N–C, where uniform CoSe nanoparticles are supported and enwrapped by single atomic Co doped carbon backbones. CoSe/Co–N–C demonstrates superior HER activities in the entire pH range, requiring small overpotentials of 71 mV, 63 mV, and 128 mV to drive a current density of 10 mA cm⁻² in 1.0 M KOH, 0.5 M H₂SO₄, and 1.0 M PBS, respectively. Moreover, remarkable long-time stabilities are achieved in all electrolytes, thanks to the attenuated corrosion with the carbon layer encapsulation derived from the fluid catalytic cracking slurry. To elucidate the interaction mechanism, theoretical calculations reveal an apparent electron transfer at CoSe and Co–N–C interfaces, which modulates the electronic structures to realize the improved intrinsic HER activities. The synergistic advances of excellent activity and remarkable stability in a wide range of pHs present its great potential for practical hydrogen mass production.

We report the synthesis and analysis of a series of conjugated ladder-type heteroarene model π-donor compounds, followed by computational and experimental mechanistic investigations of their π–π interactions and doping processes with the electron-deficient dopant F ₄ TCNQ.

It is urgently desired yet challenging to synthesize porous graphitic carbon (PGC) in a bottom-up manner while circumventing the need for high-temperature pyrolysis. Here we present an effective and scalable strategy to synthesize PGC through acid-mediated aldol triple condensation followed by low-temperature graphitization. The deliberate structural design enables its graphitization in situ in solution and at low pyrolysis temperature. The resulting material features ultramicroporosity characterized by a sharp pore size distribution. In addition, the pristine homogeneous composition of the reaction mixture allows for solution-processability of the material for further characterization and applications. Thin films of this PGC exhibit several orders of magnitude higher electrical conductivity compared to analogous control materials that are carbonized at the same temperatures. The integration of low-temperature graphitization and solution-processability not only allows for an energy-efficient method for the production and fabrication of PGC, but also paves the way for its wider employment in applications such as electrocatalysis, sensing, and energy storage.

Aromatic porous polymer networks (PPNs) are promising candidate materials for organic solvent nanofiltration (OSN) membranes, in which molecular-sieving selectivity, high permeability, and chemical/structural stability can be integrated. In this work, aromatic PPN membranes p-PPN, m-PPN and tri-PPN are fabricated by in situ aldol triple condensation cross-linking. These membranes demonstrate high stability, permeability and sharp selectivity in OSN, thanks to the aromatic nature of the backbone, high surface area (up to 1235 m² g⁻¹), and narrowly distributed pore sizes. They possess a high organic solvent permeability so that a good permeance is achieved despite a thickness of over 100 μm. The molecular weight cut-off and molecular weight retention onset of these membranes are ∼600 g mol⁻¹ and 350 g mol⁻¹, respectively, making it possible to efficiently separate molecules from a complex mixture composed of compounds with only marginally different molecular weights. As a result of the highly stable nature of the aromatic backbones, these PPN membranes show retained structural integrity and OSN performance in the presence of either a strong acid or strong base for over 50 h. The extraordinary stability integrated with excellent permeability and selectivity renders these PPN membranes promising candidates for challenging OSN applications under extreme conditions.