Advanced Thermal Interface Materials: Insights into Low-Temperature Sintering and High Thermal Conductivity of MgO.

The escalating frequency of electric vehicle (EV) fires has underscored the critical importance of effective thermal-management in battery package (TMBP). A key challenge in current TMBP lies with the low thermal conductivity (TC, 3 W m K) of commercial alumina-polymer composite (thermal interface materials, TIM). While magnesia (MgO) TIMs, which show high TC (8-10 W m K, this study) and low cost, are emerging as an alternative heat-dissipation material (HDM), their full potential remains untapped.

Suppressing Metal Dissolution in Multi-Grained Catalysts Through Intragrain Atomic Ordering for Stable Fuel Cells.

Rational design of catalytic nanomaterials is essential for developing high-performance fuel cell catalysts. However, structural degradation and elemental dissolution during operation pose significant challenges to achieving long-term stability. Herein, the development of multi-grained NiPt nanocatalysts featuring an atomically ordered NiPt phase within intragrain is reported.

Elucidating and controlling phase integration factors in Co-free Li-rich layered cathodes for lithium-ion batteries.

Li- and Mn-rich layered oxides (LLOs) with a Co-free composition are promising candidates for next-generation cathodes in low-cost and high-energy-density lithium-ion batteries. Despite their potential, the commercialization of Co-free LLOs encounters several electrochemical challenges, such as low activity and initial coulombic efficiency of the first activation cycle and compromised cycle retention, which are primarily attributed to the poor phase integrity between LiTMO and LiMnO domains. In this study, we identified that the compromised phase integrity in Co-free LLOs can be driven by the sticking Ni compositional design, which induces Li-Ni site-exchange defects in the LiTMO domain, leading to severe TMO slab mismatches between phases and resulting in a penalty in enthalpy mixing energy.

Optimizing Carbon Coating Process for Lithium-Rich LiFePO Cathode Materials.

LiFePO (Li-rich LFP) has been proposed as an alternative to address low ionic and electronic conductivity of stoichiometric LiFePO (LFP). However, comprehensive studies investigating the impact of the carbon coating process on crystal structure and electrochemical performance during the synthesis of Li-rich LFP are still lacking. In particular, the characteristics of carbon precursor and calcination atmosphere significantly influence formation of crystal structure and electrochemical properties of the Li-rich LFP, underlining the necessity for further investigation.

Understanding mechanical failure behaviours and protocol optimization for fast charging applications in Co-free Ni-based cathodes for lithium-ion batteries.

Currently, it is a significant challenge to achieve long-term cyclability and fast chargeability in lithium-ion batteries, especially for the Ni-based oxide cathode, due to severe chemo-mechanical degradation. Despite its importance, the fast charging long-term cycling behaviour is not well understood. Therefore, we comprehensively evaluate the feasibility of fast charging applications for Co-free layered oxide cathodes, with a focus on the extractable capacity and cyclability.

Ferromagnetic stability optimization via oxygen-vacancy control in single-atom Co/TiO nanostructures.

Oxygen vacancies and their correlation with the nanomagnetism and electronic structure are crucial for applications in dilute magnetic semiconductors design applications. Here, we report on cobalt single atom-incorporated titanium dioxide (TiO) monodispersed nanoparticles synthesized using a thermodynamic redistribution strategy. Using advanced synchrotron-based X-ray techniques and simulations, we find trivalent titanium is absent, indicating trivalent cations do not influence ferromagnetic (FM) stability.

Enhancing P2/O3 Biphasic Cathode Performance for Sodium-Ion Batteries: A Metaheuristic Approach to Multi-Element Doping Design.

Sodium-ion batteries (SIBs) have emerged as a compelling alternative to lithium-ion batteries (LIBs), exhibiting comparable electrochemical performance while capitalizing on the abundant availability of sodium resources. In SIBs, P2/O3 biphasic cathodes, despite their high energy, require furthur improvements in stability to meet current energy demands. This study introduces a systematic methodology that leverages the meta-heuristically assisted NSGA-II algorithm to optimize multi-element doping in electrode materials, aiming to transcend conventional trial-and-error methods and enhance cathode capacity by the synergistic integration of P2 and O3 phases.

Nanocrystalline Composite Layer Realized by Simple Sintering Without Surface Treatment, Reducing Hydrophilicity and Increasing Thermal Conductivity.

The surface treatment for a polymer-ceramic composite is additionally performed in advanced material industries. To prepare the composite without a surface treatment, the simplest way to manufacture an advanced ceramic-particle is devised. The method is the formation of a nanocrystalline composite layer through the simple liquid-phase sintering.

Unprecedented Cyclability and Moisture Durability of NaCrO Sodium-Ion Battery Cathode via Simultaneous Al Doping and CrO Coating.

Although there are many cathode candidates for sodium-ion batteries (NIBs), NaCrO remains one of the most attractive materials due to its reasonable level of capacity, nearly flat reversible voltages, and high thermal stability. However, the cyclic stability of NaCrO needs to be further improved in order to compete with other state-of-the-art NIB cathodes. In this study, we show that CrO-coated and Al-doped NaCrO, which is synthesized through a simple one-pot synthesis, can achieve unprecedented cyclic stability.

NaZrFe(PO)─A Rhombohedral NASICON-Structured Material: Synthesis, Structure and Na-Intercalation Behavior.

A NASICON-structured earth-abundant mixed transition metal (T) containing Na-T-phosphate, viz., NaZrFe(PO), has been prepared via a sol-gel route using a low-cost Fe-based precursor. The as-prepared material crystallizes in the desired rhombohedral NASICON structure (space group: 3̅) at room temperature.

Synchrotron radiation based X-ray techniques for analysis of cathodes in Li rechargeable batteries.

Li-ion rechargeable batteries are promising systems for large-scale energy storage solutions. Understanding the electrochemical process in the cathodes of these batteries using suitable techniques is one of the crucial steps for developing them as next-generation energy storage devices. Due to the broad energy range, synchrotron X-ray techniques provide a better option for characterizing the cathodes compared to the conventional laboratory-scale characterization instruments.

Optimal Composition of Li Argyrodite with Harmonious Conductivity and Chemical/Electrochemical Stability: Fine-Tuned Via Tandem Particle Swarm Optimization.

A tandem (two-step) particle swarm optimization (PSO) algorithm is implemented in the argyrodite-based multidimensional composition space for the discovery of an optimal argyrodite composition, i.e., with the highest ionic conductivity (7.

Unravelling the Nature of the Intrinsic Complex Structure of Binary-Phase Na-Layered Oxides.

The layered sodium transition metal oxide, NaTMO (TM = transition metal), with a binary or ternary phases has displayed outstanding electrochemical performance as a new class of strategy cathode materials for sodium-ion batteries (SIBs). Herein, an in-depth phase analysis of developed Na TMO cathode materials, Na Ni Fe Mn O with P2- and O3-type phases (NFMO-P2/O3) is offered. Structural visualization on an atomic scale is also provided and the following findings are unveiled: i) the existence of a mixed-phase intergrowth layer distribution and unequal distribution of P2 and O3 phases along two different crystal plane indices and ii) a complete reversible charge/discharge process for the initial two cycles that displays a simple phase transformation, which is unprecedented.

Mn-Dopant Differentiating the Ru and Ir Oxidation States in Catalytic Oxides Toward Durable Oxygen Evolution Reaction in Acidic Electrolyte.

Designing an efficient and durable electrocatalyst for the sluggish oxygen evolution reaction (OER) at the anode remains the foremost challenge in developing proton exchange membrane (PEM) electrolyzers. Here, a highly active and durable cactus-like nanoparticle with an exposed heterointerface between the IrO and the low oxidation state Ru by introducing a trace amount of Mn dopant is reported. The heterostructure fabrication relies on initial mixing of the Ru and Ir phases before electrochemical oxidation to produce a conjoined Ru/IrO heterointerface.

Oxygen-Vacancy-Driven Orbital Reconstruction at the Surface of TiO Core-Shell Nanostructures.

Oxygen vacancies and their correlation with the electronic structure are crucial to understanding the functionality of TiO nanocrystals in material design applications. Here, we report spectroscopic investigations of the electronic structure of anatase TiO nanocrystals by employing hard and soft X-ray absorption spectroscopy measurements along with the corresponding model calculations. We show that the oxygen vacancies significantly transform the Ti local symmetry by modulating the covalency of titanium-oxygen bonds.

Soft X-ray Absorption Spectroscopic Investigation of Li(NiCoMn)O Cathode Materials.

Herein, we report the soft X-ray absorption spectroscopic investigation for Li(NiCoMn)O cathode material during charging and discharging. These measurements were carried out at the Mn -, Co -, and Ni -edges during various stages of charging and discharging. Both the Mn and Co -edge spectroscopic measurements reflect the invariance in the oxidation states of Mn and Co ions.

Graphite as a Long-Life Ca-Intercalation Anode and its Implementation for Rocking-Chair Type Calcium-Ion Batteries.

Herein, graphite is proposed as a reliable Ca-intercalation anode in tetraglyme (G). When charged (reduced), graphite accommodates solvated Ca-ions (Ca-G) and delivers a reversible capacity of 62 mAh g that signifies the formation of a ternary intercalation compound, Ca-G·C. Mass/volume changes during Ca-G intercalation and the evolution of in operando X-ray diffraction studies both suggest that Ca-G intercalation results in the formation of an intermediate phase between stage-III and stage-II with a gallery height of 11.

KCrS Cathode with Considerable Cyclability and High Rate Performance: The First K Stoichiometric Layered Compound for Potassium-Ion Batteries.

KCrS is presented as a stable and high-rate layered material that can be used as a cathode in potassium-ion batteries. As far as it is known, KCrS is the only layered material with stoichiometric amounts of K , which enables coupling with a graphite anode for full-cell construction. Cr(III)/Cr(IV) redox in KCrS is also unique, because LiCrS and NaCrS are known to experience S /S redox.

High-resolution patterning of solution-processable materials via externally engineered pinning of capillary bridges.

Electronics based on solution-processable materials are promising for applications in many fields which stimulated enormous research interest in liquid-drying and pattern formation. However, assembling of structure with submicrometre/nanometre resolution through liquid process is very challenging. We show a simple method to rapidly generate polymer structures with deep-submicrometre-sized features over large areas.

Unraveling the Magnesium-Ion Intercalation Mechanism in Vanadium Pentoxide in a Wet Organic Electrolyte by Structural Determination.

Magnesium batteries have received attention as a type of post-lithium-ion battery because of their potential advantages in cost and capacity. Among the host candidates for magnesium batteries, orthorhombic α-VO is one of the most studied materials, and it shows a reversible magnesium intercalation with a high capacity especially in a wet organic electrolyte. Studies by several groups during the last two decades have demonstrated that water plays some important roles in getting higher capacity.

Red green blue emissive lead sulfide quantum dots: heterogeneous synthesis and applications.

Visible emission colloidal quantum dots (QDs) have shown promise in optical and optoelectronic applications. These QDs are typically composed of relatively expensive elements in the form of indium, cadmium, and gallium since alternative candidate materials exhibiting similar properties are yet to be realized. Herein, for the first time, we report red green blue (RGB) photoluminescences with quantum yields of 18% from earth-abundant lead sulfide (PbS) QDs.

Inhibition of methane and natural gas hydrate formation by altering the structure of water with amino acids.

Natural gas hydrates are solid hydrogen-bonded water crystals containing small molecular gases. The amount of natural gas stored as hydrates in permafrost and ocean sediments is twice that of all other fossil fuels combined. However, hydrate blockages also hinder oil/gas pipeline transportation, and, despite their huge potential as energy sources, our insufficient understanding of hydrates has limited their extraction.

Effects of Ag-embedment on electronic and ionic conductivities of LiMnPO4 and its performance as a cathode for lithium-ion batteries.

An Ag-embedded LiMnPO4 (LMP) cathode was synthesized by solid-state reaction using a 1 wt% Ag precursor. Structure, morphology, and electrical conductivity studies of Ag-embedded LMP were performed by high resolution powder X-ray diffraction, high resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, and four probe measurements. An Ag nanoparticle (∼26 nm) surrounded by several olivine crystallites within a single particle dramatically improved the overall electrical conductivity of LMP by four orders of magnitude relative to that of pristine LMP, playing roles as conducting bridges among LMP crystallites as well as particles.

Gas hydrate inhibition by perturbation of liquid water structure.

Natural gas hydrates are icy crystalline materials that contain hydrocarbons, which are the primary energy source for this civilization. The abundance of naturally occurring gas hydrates leads to a growing interest in exploitation. Despite their potential as energy resources and in industrial applications, there is insufficient understanding of hydrate kinetics, which hinders the utilization of these invaluable resources.