能源化学最新文献

Self-assembly of metal halide perovskite nanocrystals (NCs) into superlattices can exhibit unique collective properties, which have significant application values in the display, detector, and solar cell field. This review discusses the driving forces behind the self-assembly process of perovskite NCs, and the commonly used self-assembly methods and different self-assembly structures are detailed. Subsequently, we summarize the collective optoelectronic properties and application areas of perovskite superlattice structures. Finally, we conclude with an outlook on the potential issues and future challenges in developing perovskite NCs.

Nafion as a universal polymer ionomer was widely applied for nanocatalysts electrode preparation. However, the effect of Nafion on electrocatalytic performance was often overlooked, especially for CO₂ electrolysis. Herein, the key roles of Nafion for CO₂RR were systematically studied on Cu nanoparticles (NPs) electrocatalyst. We found that Nafion modifier not only inhibit hydrogen evolution reaction (HER) by decreasing the accessibility of H₂O from electrolyte to Cu NPs, and increase the CO₂ concentration at electrocatalyst interface for enhancing the CO₂ mass transfer process, but also activate CO₂ molecule by Lewis acid-base interaction between Nafion and CO₂ to accelerate the formation of *CO, which favor of C–C coupling for boosting C₂ product generation. Owing to these features, the HER selectivity was suppressed from 40.6% to 16.8% on optimal Cu@Nafion electrode at −1.2 V versus reversible hydrogen electrode (RHE), and as high as 73.5% faradaic efficiencies (FEs) of C₂ products were achieved at the same applied potential, which was 2.6 times higher than that on bare Cu electrode (∼28.3%). In addition, Nafion also contributed to the long-term stability by hinder Cu NPs morphology reconstruction. Thus, this work provides insights into the impact of Nafion on electrocatalytic CO₂RR performance.

With the rapid development of rechargeable metal-ion batteries (MIBs) with safety, stability and high energy density, significant efforts have been devoted to exploring high-performance electrode materials. In recent years, two-dimensional (2D) molybdenum-based (Mo-based) materials have drawn considerable attention due to their exceptional characteristics, including low cost, unique crystal structure, high theoretical capacity and controllable chemical compositions. However, like other transition metal compounds, Mo-based materials are facing thorny challenges to overcome, such as slow electron/ion transfer kinetics and substantial volume changes during the charge and discharge processes. In this review, we summarize the recent progress in developing emerging 2D Mo-based electrode materials for MIBs, encompassing oxides, sulfides, selenides, carbides. After introducing the crystal structure and common synthesis methods, this review sheds light on the charge storage mechanism of several 2D Mo-based materials by various advanced characterization techniques. The latest achievements in utilizing 2D Mo-based materials as electrode materials for various MIBs (including lithium-ion batteries (LIBs), sodium-ion batteries (SIBs) and zinc-ion batteries (ZIBs)) are discussed in detail. Afterwards, the modulation strategies for enhancing the electrochemical performance of 2D Mo-based materials are highlighted, focusing on heteroatom doping, vacancies creation, composite coupling engineering and nanostructure design. Finally, we present the existing challenges and future research directions for 2D Mo-based materials to realize high-performance energy storage systems.

Metal-organic frameworks (MOFs) are among the most promising materials for lithium-ion batteries (LIBs) owing to their high surface area, periodic porosity, adjustable pore size, and controllable chemical composition. For instance, their unique porous structures promote electrolyte penetration, ions transport, and make them ideal for battery separators. Regulating the chemical composition of MOF can introduce more active sites for electrochemical reactions. Therefore, MOFs and their related composites have been extensively and thoroughly explored for LIBs. However, the reported reviews solely include the applications of MOFs in the electrode materials of LIBs and rarely involve other aspects. A systematic review of the application of MOFs in LIBs is essential for understanding the mechanism of MOFs and better designing related MOFs battery materials. This review systematically evaluates the latest developments in pristine MOFs and MOF composites for LIB applications, including MOFs as the main materials (anode, cathode, separators, and electrolytes) to auxiliary materials (coating layers and additives for electrodes). Furthermore, the synthesis, modification methods, challenges, and prospects for the application of MOFs in LIBs are discussed.

Zeolite-encapsulated metal nanoclusters are at the heart of bifunctional catalysts, which hold great potential for petrochemical conversion and the emerging sustainable biorefineries. Nevertheless, efficient encapsulation of metal nanoclusters into a high-silica zeolite Y in particular with good structural integrity still remains a significant challenge. Herein, we have constructed Ru nanoclusters (∼1 nm) encapsulated inside a high-silica zeolite Y (SY) with a SiO₂/Al₂O₃ ratio (SAR) of 10 via a cooperative strategy for direct zeolite synthesis and a consecutive impregnation for metal encapsulation. Compared with the benchmark Ru/H-USY and other analogues, the as-prepared Ru/H-SY markedly boosts the yields of pentanoic biofuels and stability in the direct hydrodeoxygenation of biomass-derived levulinate even at a mild temperature of 180 °C, which are attributed to the notable stabilization of transition states by the enhanced acid accessibility and properly sized constraints of zeolite cavities owing to the good structural integrity.

The unparalleled energy density has granted lithium-sulfur batteries (LSBs) with attractive usages. Unfortunately, LSBs still face some unsurpassed challenges in industrialization, with polysulfides shuttling, dendrite growth and thermal hazard as the major problems triggering the cycling instability and low safety. With the merit of convenience, the method of designing functional separator has been adapted. Concretely, the carbon aerogel confined with CoS₂ (CoS₂-NCA) is constructed and coated on Celgard separator surface, acquiring CoS₂-NCA modified separator (CoS₂-NCA@C), which holds the promoted electrolyte affinity and flame retardance. As revealed, CoS₂-NCA@C cell gives a high discharge capacity 1536.9 mAh/g at 1st cycle, much higher than that of Celgard cell (987.1 mAh/g). Moreover, the thermal runaway triggering time is dramatically prolonged by 777.4 min, corroborating the promoted thermal safety of cell. Noticeably, the higher coulombic efficiency stability and lower overpotential jointly confirm the efficacy of CoS₂-NCA@C in suppressing the lithium dendrite growth. Overall, this work can provide useful inspirations for designing functional separator, coping with the vexing issues of LSBs.

Silver-copper electrocatalysts have demonstrated effectively catalytic performance in electroreduction CO₂ toward CH₄, yet a revealing insight into the reaction pathway and mechanism has remained elusive. Herein, we construct chemically bonded Ag-Cu₂O boundaries, in which the complete reduction of Cu₂O to Cu has been strongly impeded owing to the presence of surface Ag shell. The interfacial confinement effect helps to maintain Cu⁺ sites at the Ag-Cu₂O boundaries. Using in situ/operando spectroscopy and theoretical simulations, it is revealed that CO₂ is enriched at the Ag-Cu₂O boundaries due to the enhanced physisorption and chemisorption to CO₂, activating CO₂ to form the stable intermediate *CO. The boundaries between Ag shell and the Cu₂O mediate local *CO coverage and promote *CHO intermediate formation, consequently facilitating CO₂-to-CH₄ conversion. This work not only reveals the structure-activity relationships but also offers insights into the reaction mechanism on Ag-Cu catalysts for efficient electrocatalytic CO₂ reduction.

LiMn₂O₄ (LMO) electrochemical lithium-ion pump has gained widespread attention due to its green, high efficiency, and low energy consumption in selectively extracting lithium from brine. However, collapse of crystal structure and loss of lithium extraction capacity caused by Mn dissolution loss limits its industrialized application. Hence, a multifunctional coating was developed by depositing amorphous AlPO₄ on the surface of LMO using sol-gel method. The characterization and electrochemical performance test provided insights into the mechanism of Li⁺ embedment and de-embedment and revealed that multifunctional AlPO₄ can reconstruct the physical and chemical state of LMO surface to improve the interface hydrophilicity, promote the transport of Li⁺, strengthen cycle stability. Remarkably, after 20 cycles, the capacity retention rate of 0.5AP-LMO reached 93.6% with only 0.147% Mn dissolution loss. The average Li⁺ release capacity of 0.5AP-LMO//Ag system in simulated brine is 28.77 mg/(g h), which is 90.4% higher than LMO. Encouragingly, even in the more complex Zabuye real brine, 0.5AP-LMO//Ag can still maintain excellent lithium extraction performance. These results indicate that the 0.5AP-LMO//Ag lithium-ion pump shows promising potential as a Li⁺ selective extraction system.

Direct growth of redox-active noble metals and rational design of multifunctional electrochemical active materials play crucial roles in developing novel electrode materials for energy storage devices. In this regard, silver (Ag) has attracted great attention in the design of efficient electrodes. Inspired by the house/building process, which means electing the right land, it lays a strong foundation and building essential columns for a complex structure. Herein, we report the construction of multifaceted heterostructure cobalt-iron hydroxide (CFOH) nanowires (NWs)@nickel cobalt manganese hydroxides and/or hydrate (NCMOH) nanosheets (NSs) on the Ag-deposited nickel foam and carbon cloth (i.e., Ag/NF and Ag/CC) substrates. Moreover, the formation and charge storage mechanism of Ag are described, and these contribute to good conductive and redox chemistry features. The switching architectural integrity of metal and redox materials on metallic frames may significantly boost charge storage and rate performance with noticeable drop in resistance. The as-fabricated Ag@CFOH@NCMOH/NF electrode delivered superior areal capacity value of 2081.9 µA h cm⁻² at 5 mA cm⁻². Moreover, as-assembled hybrid cell based on NF (HC/NF) device exhibited remarkable areal capacity value of 1.82 mA h cm⁻² at 5 mA cm⁻² with excellent rate capability of 74.77% even at 70 mA cm⁻² Furthermore, HC/NF device achieved maximum energy and power densities of 1.39 mW h cm⁻² and 42.35 mW cm⁻², respectively. To verify practical applicability, both devices were also tested to serve as a self-charging station for various portable electronic devices.

Lithium sulfur (Li-S) battery is a kind of burgeoning energy storage system with high energy density. However, the electrolyte-soluble intermediate lithium polysulfides (LiPSs) undergo notorious shuttle effect, which seriously hinders the commercialization of Li-S batteries. Herein, a unique VSe₂/V₂C heterostructure with local built-in electric field was rationally engineered from V₂C parent via a facile thermal selenization process. It exquisitely synergizes the strong affinity of V₂C with the effective electrocatalytic activity of VSe₂. More importantly, the local built-in electric field at the heterointerface can sufficiently promote the electron/ion transport ability and eventually boost the conversion kinetics of sulfur species. The Li-S battery equipped with VSe₂/V₂C-CNTs-PP separator achieved an outstanding initial specific capacity of 1439.1 mA h g⁻¹ with a high capacity retention of 73% after 100 cycles at 0.1 C. More impressively, a wonderful capacity of 571.6 mA h g⁻¹ was effectively maintained after 600 cycles at 2 C with a capacity decay rate of 0.07%. Even under a sulfur loading of 4.8 mg cm⁻², areal capacity still can be up to 5.6 mA h cm⁻². In-situ Raman tests explicitly illustrate the effectiveness of VSe₂/V₂C-CNTs modifier in restricting LiPSs shuttle. Combined with density functional theory calculations, the underlying mechanism of VSe₂/V₂C heterostructure for remedying LiPSs shuttling and conversion kinetics was deciphered. The strategy of constructing VSe₂/V₂C heterocatalyst in this work proposes a universal protocol to design metal selenide-based separator modifier for Li-S battery. Besides, it opens an efficient avenue for the separator engineering of Li-S batteries.