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Organic carbonyl electrode materials offer promising prospects for future energy storage systems due to their high theoretical capacity, resource sustainability, and structural diversity. Although much progress has been made in the research of high-performance carbonyl electrode materials, systematic and in-depth studies on the underlying factors affecting their electrochemical properties are rather limited. Herein, five polyimides containing different types of diamine linkers are designed and synthesized as cathode materials for Li-ion batteries. First, the incorporation of carbonyl groups increases the active-site density in both conjugated and non-conjugated systems. Second, increased molecular rigidity can improve the accessibility of the active sites. Third, the introduction of the conjugated structure between two carbonyl groups can increase the reactivity of the active sites. Consequently, the incorporation of carbonyl structures and conjugated structures increases the capacity of polyimides. PTN, PAN, PMN, PSN, and PBN exhibit 212, 198, 199, 151, and 115 ​mAh ​g⁻¹ ​at 50 ​mA ​g⁻¹, respectively. In addition, the introduction of a carbonyl structure and a conjugated structure is also beneficial for improving cycling stability and rate performance. This work can deepen the understanding of the structure–function relationship for the rational design of polyimide electrode materials and can be extended to the molecular design of other organic cathode materials.

Metal anodes (e.g., Li and Zn) are promising candidates for high-energy and high-power rechargeable batteries. However, the commercialization of metal anodes is hampered by irregular dendrite growth, which severely deteriorates the safety and cyclability of metal anodes. Optimizing the electrolyte by nanostructured additives to regulate the metal deposition shows great potential since the electrochemically nonreactive feature endows the regulation function with good sustainability. In this manuscript, the fundamental dendrite formation models and key parameters for stabilizing metal anode are first discussed. The progress and functional mechanism of nanostructured additives for regulating the metal deposition are summarized in terms of regulatory model, i.e., deposition-, adsorption- and dispersion-type. Finally, we also provide a detailed concluding outlook, pointing out the future trend of selecting new nanostructured additive candidates and elucidating synergistic effects and underlying mechanisms with the key attention being given to the assessments of practicality.

Despite the widespread utilization of Lithium-ion batteries (LIBs), concerns regarding safety during operation persist owing to accidents and potential risks of fires and explosions. To comprehend the thermal dynamics that underlie severe LIB incidents, calorimetry tests have been prevalently employed for over three decades to examine the exothermic/endothermic behavior, reaction kinetics, and thermal interactions among LIB materials. There exists a substantial volume of calorimetry test results on various LIB electrodes, electrolytes, and other components. However, this data showcases low consistency, yielding an unreliable database that obstructs a thorough understanding of LIB thermal behavior. In this research, a comparative analysis of differential scanning calorimetry (DSC) results from materials utilized in the most commercialized LIB systems is conducted. The analysis unveils notable discrepancies in DSC data amassed by different researchers, identifies five predominant causes of data inconsistency, proposes a standardized DSC operational procedure, and generates a set of self-consistent data. Subsequently, an intrinsic safety spectrum is delineated and compared with X-ray diffraction (XRD) outcomes to elucidate the correlation between the crystal lattice structure and the thermal behavior of the material. This work aids in the formation of a comparative DSC database, utilizing the vast but inconsistent literature data. Moreover, it clarifies the linkage between the material structure and thermal behavior, facilitating data-driven thermal analysis of LIBs.

Single-crystalline layered oxide materials for lithium-ion batteries are featured by their excellent capacity retention over their polycrystalline counterparts, making them sought-after cathode candidates. Their capacity degradation, however, becomes more severe under high-voltage cycling, hindering many high-energy applications. It has long been speculated that the interplay among composition heterogeneity, lattice deformation, and redox stratification could be a driving force for the performance decay. The underlying mechanism, however, is not well-understood. In this study, we use X-ray microscopy to systematically examine single-crystalline NMC particles at the mesoscale. This technique allows us to capture detailed signals of diffraction, spectroscopy, and fluorescence, offering spatially resolved multimodal insights. Focusing on early high-voltage charging cycles, we uncover heterogeneities in valence states and lattice structures that are inherent rather than caused by electrochemical abuse. These heterogeneities are closely associated with compositional variations within individual particles. Our findings provide useful insights for refining material synthesis and processing for enhanced battery longevity and efficiency.

Solid-state batteries (SSBs) have received widespread attention with their high safety and high energy density characteristics. However, solid-solid contacts in the internal electrode material and the electrode material/solid electrolyte (SE) interfaces, as well as the severe electrochemo-mechanical effects caused by the internal stress due to the volume change of the active material, these problems hinder ion/electron transport within the SSBs, which significantly deteriorates the electrochemical performance. Applying fabrication pressures and stack pressures are effective measures to improve solid-solid contact and solve electrochemo-mechanical problems. Herein, the influences of different pressures on cathode material, anode material, SEs, and electrode/SEs interface are briefly summarized from the perspective of interface ion diffusion, transmission of electrons and ions in internal particles, current density and ion diffusion kinetics, and the volume changes of Li⁺ stripping/plating based on two physical contact models, and point out the direction for the future research direction of SSBs and advancing industrialization by building the relationship between pressures and SSBs electrochemistry.

In response to the current energy and environmental challenges, reducing or replacing reliance on fossil fuels and striving for carbon neutrality seems to be the only viable choice. Recently, a cutting-edge, eco-friendly method of chemical synthesis via transient Joule heating (JH) demonstrated significant promise across various domains, including methane reforming, ammonia synthesis, volatile organic compounds removal, plastic recycling, the synthesis of functional carbon materials from repurposed solid waste, etc. In this review, the advantages, and latest developments in thermochemical synthesis by flash and transient JH are comprehensively outlined. Unlike the ongoing heating process of conventional furnaces that consume fossil fuels, dynamic and transient JH can get significantly higher reaction rates, energy efficiency, flexibility, and versatility. Subsequently, the transient reaction mechanism, data science optimization, and scale-up production models are discussed, and prospects for the integration of the electrified chemical industry with renewable energy for carbon neutrality and long-term energy storage are also envisioned.

Lithium metal anodes (LMAs) have been considered the ultimate anode materials for next-generation batteries. However, the uncontrollable lithium dendrite growth and huge volume expansion that can occur during charge and discharge seriously hinder the practical application of LMAs. Metal–organic framework (MOF) materials, which possess the merits of huge specific surface area, excellent porosity, and flexible composition/structure tunability, have demonstrated great potential for resolving both of these issues. This article first explores the mechanism of lithium dendrite formation as described by four influential models. Subsequently, based on an in-depth understanding of these models, we propose potential strategies for utilizing MOFs and their derivatives to suppress lithium dendrite growth. We then provide a comprehensive review of research progress with respect to various applications of MOFs and their derivatives to suppress lithium dendrites and inhibit volume expansion. The paper closes with a discussion of perspectives on future modifications of MOFs and their derivatives to achieve stable and dendrite-free lithium metal batteries.

The usage of cheap crude H₂ in proton-exchange membrane fuel cells (PEMFCs) is still unrealistic to date, due to the suffering of the current Pt based nano-catalysts from impurities such as CO in anode. Recently, synergistic active sites between single atom (SA) and nanoparticle (NP) have been found to be promising for overcoming the poisoning problem. However, lengthening the nanoparticle-single atom (SA–NP) interface, i.e., constructing high density synergistic active sites, remains highly challenging. Herein, we present a new strategy based on molecular fusion strategy to create abundant SA–NP interfaces, with high density SA–NP interfaces created on a two dimensional nitrogen doped carbon nanosheets (Ir-SACs&NPs/NC). Owing to the abundance of SA–NP interface sites, the catalyst was empowered with a high tolerance towards up to 1000 ​ppm CO in H₂ feed. These findings provide guidelines for the design and construction of active and anti-poisoning catalysts for PEMFC anode.

Free radicals can improve the reaction rate, but most of them are unstable due to unpaired electrons. Simultaneously maintaining their stability and activity is challenging. Herein, taking sulfur (S) radicals as an example, we propose a strategy in which solvated metal complexes constructed by Al(acetylacetonate)₃ and different solvents can stabilize high concentrations of S radicals with good activity through ion–dipole interactions. Based on this strategy, it is first demonstrated that ${S_4}^{·-}$ is selectively stabilized by controlling the configurations of the solvated complexes. As a result, the reaction rate of S↔Li₂S is increased by 8 times, and the energy efficiency and rate capability of the Li–S batteries are significantly improved, especially the 5-fold increase in cell capacities at a low electrolyte/sulfur ratio. This work provides an important strategy in which solvated metal complexes balance the activity and stability of free radicals to accelerate reactions and their application in various fields.