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Understanding the nucleation and growth mechanisms of highentropy alloy (HEA) nanoparticles is crucial for developing functional nanocrystals with tailored properties. This study investigates the thermal decomposition of mixed metal salt precursors (Fe, Ni, Pt, Ir, Ru) on reduced graphene oxide (rGO) using in situ transmission electron microscopy (TEM) when heated to 1000 °C at both slow (20 °C min−1) and fast (103 °C s−1) heating/cooling rates. Slow heating to 1000 °C revealed the following: (1) The nanoparticles' nucleation occurred through multistage decomposition at lower temperatures (250−300 °C) than single metal salt precursors (300−450 °C). (2) Pt-dominant nanocrystals autocatalytically reduced other elements, leading to the formation of multimetallic FeNiPtIrRu nanoparticles. (3) At 1000 °C, the nanoparticles were single-phase with noble metals enriched compared to transition metals. (4) Slow cooling induced structural heterogeneity and phase segregation due to element diffusion and thermodynamic miscibility. (5) Adding polyvinylpyrrolidone (PVP) suppressed segregation, promoting HEA nanoparticle formation even during slow cooling by limiting atomic diffusion. Under fast heating/cooling, nanoparticles formed as a solid solution of fcc HEA, indicating kinetic control and limited atomic diffusion. The density function theory (DFT) calculations illustrate that the simultaneous presence of metal elements on rGO, as expected by the fast heating process, favors the formation of an fcc HEA structure, with strong interactions between HEA nanoparticles and rGO enhancing stability. This study provides insights into how heating rates and additives like PVP can control phase composition, chemical homogeneity, and stability, enabling the rational design of complex nanomaterials for catalytic, energy, and functional applications. 

Abstract A comprehensive understanding of the solid‐electrolyte interphase (SEI) in lithium‐ion batteries is crucial for improving energy efficiency, battery performance, and safety. In this study, a transformer‐based instance segmentation framework, integrating deep convolutional neural networks is introduced with a feature pyramid network (FPN), to quantitatively analyze High‐Resolution Transmission Electron Microscopy (HRTEM) images and explain the complex microstructural features of the SEI. The model is trained on a dataset of simulated HRTEM images generated using Density Functional Theory (DFT)‐optimized grain boundary (GB) structures and calibrated with experimental microscope parameters. The model achieves robust segmentation performance, with training and validation mean intersection over union (mIOU) values of 0.98 and 0.96, respectively. On unseen test data, the model attains mean area match (AM) scores of 91.4% for GBs, 92.3% for Li₂CO₃, 91.7% for LiF, 88.7% for LiOH, and 88.6% for Li₂O. These quantitative results highlight the model's high fidelity and its ability to capture subtle variations in crystallographic orientations and material contrasts. By enabling detailed, statistically grounded segmentation of SEI components, the approach offers valuable insights into ion transport and degradation mechanisms, paving the way for more resilient and efficient energy storage solutions. 

High-entropy materials (HEMs) constitute a revolutionary class of materials that have garnered significant attention in the field of materials science, exhibiting extraordinary properties in the realm of energy storage. These equimolar multielemental compounds have demonstrated increased charge capacities, enhanced ionic conductivities, and a prolonged cycle life, attributed to their structural stability. In the anode, transitioning from the traditional graphite (372 mAh g−1) to an HEM anode can increase capacity and enhance cycling stability. For cathodes, lithium iron phosphate (LFP) and nickel manganese cobalt (NMC) can be replaced with new cathodes made from HEMs, leading to greater energy storage. HEMs play a significant role in electrolytes, where they can be utilized as solid electrolytes, such as in ceramics and polymers, or as new high-entropy liquid electrolytes, resulting in longer cycling life, higher ionic conductivities, and stability over wide temperature ranges. The incorporation of HEMs in metal–air batteries offers methods to mitigate the formation of unwanted byproducts, such as Zn(OH)4 and Li2CO3, when used with atmospheric air, resulting in improved cycling life and electrochemical stability. This review examines the basic characteristics of HEMs, with a focus on the various applications of HEMs for use as different components in lithium-ion batteries. The electrochemical performance of these materials is examined, highlighting improvements such as specific capacity, stability, and a longer cycle life. The utilization of HEMs in new anodes, cathodes, separators, and electrolytes offers a promising path towards future energy storage solutions with higher energy densities, improved safety, and a longer cycling life. 

Green synthesis of micro/nanomaterials, using glycerol as a sustainable solvent, offers environmentally and health-friendly pathways. Glycerol’s versatility in a solvothermal synthesis is effective for nanoparticle production, yet its mechanistic role in carbonate material formation is unexplored. This study investigates urchin-like strontium carbonate formation via a glycerol-mediated solvothermal synthesis, employing in situ transmission electron microscopy (in situ TEM), scanning electron microscopy, density function theory (DFT), scanning transmission electron microscopy, and X-ray diffraction. In situ TEM observations unveil the initial stages of strontium hydroxide nucleation and subsequent growth as an intermediate phase. The findings suggested that the hyperbranched polymerization of glycerol plays a pivotal role in the formation of urchin-like morphology. Furthermore, the synergistic effect of glycerol and CO2 is proposed as the primary driver for the formation of strontium carbonate. Notably, observations showed a morphological transition from spherical to urchin-like with increasing reaction time. DFT studies proposed glycerol as a coadsorbent, boosting the adsorption energy of CO2 and directing its interaction with Sr(OH)2 resulting in the stable formation of SrCO3. This research provides valuable insights into the urchin-like strontium carbonate formation in a time-dependent process driven by the polymerization of glycerol and its high reactivity with dissolved CO2 at elevated temperatures. 

In response to the requirement for alternative energy conversion and storage methods, metal-glycerolates (MG) and their analogs are considered promising classes of electrode material that can be synthesized in various designs. Recently, the concept of high-entropy configuration and multimetallic systems has gained attention in the field of electrocatalysis. In fact, the presence of five or more metals in a single-phase material can produce unique and unexpected properties. Thus, it becomes crucial to explore different metal combinations and evaluate their synergistic interaction as a result of these combinations. Therefore, in this work, a scalable solvothermal method was used to synthesize a high-entropy glycerolate (HEG) containing Ni, Zn, Mn, Mg, and Co ions (HEG) and their respective sub-systems such as NiG, NiMnG, and NiMnZnG. The SEM-EDS images showed the excellent distribution of the metal cations in the obtained microspheres. Surprisingly, our experiments demonstrated that even in reaching a single-phase HEG, the oxygen evolution reaction (OER) performance measured in 1 M KOH electrolyte did not surpass the benefit effect observed in the NiG-based carbon paste with an overpotential of 310 mV (@10 mA cm–2), against 341 mV (@10 mA cm–2) of HEG. Moreover, the NiG shows good stability toward OER even after 24 h, which is attributed to the NiOOH active phase generated during the electrochemical cycling. 

Dendritic growth of lithium (Li) is hindering potential applications of Li-metal batteries, and new approaches are needed to address this challenge. The confinement effect of two-dimensional materials triggered by strong molecular interactions between parallelly-aligned graphene oxide (GO) at Li metal interface is proposed here as a new strategy to suppress the dendritic growth of Li. The effectiveness of aligned GO for Li-metal cells is shown for two different polymer separator cells:liquid electrolytes with porous propylene (PP) separators and solid polyethylene oxide (PEO) electrolytes. For the case of liquid electrolytes, PP separators were modified with plasma treatment to induce the alignment of GO layers. The Li‖Li cells with aligned GO illustrate a stable Li platting/stripping (up to 1000 cycles). The Li‖lithium iron phosphate (LFP) battery cells with aligned GO could cycle at 5C for 1000 cycles (∼90% capacity retention). For solid polymer electrolyte (SPE) cells, GO–Li confinement effect is also effective in Li dendrites suppression enhancing the stability and lifespan of Li-metal batteries. The Li‖LFP cell with the GO-modified SPE showed ∼85% capacity retention after 200 cycles at 1C. Such combined high rate capability and number of cycles exceeds the previously reported performances for both liquid and SPE-based Li‖LFP cells. This points to a new opportunity for utilizing the confinement effect of two-dimensional materials for the development of next generation, fast rate rechargeable Li batteries. 

Study of nucleation and growth dynamic events of cubic-phase ice crystals at TiO₂–water nanointerface.