Nucleation Research Articles

Controlled Oxidation of Metallic Molybdenum Patterns via Joule Heating for Localized MoS2 Growth

High-quality two-dimensional transition metal dichalcogenides (2D TMDs), such as molybdenum disulfide (MoS2), have significant potential for advanced electrical and optoelectronic applications. This study introduces a novel approach to control the localized growth of MoS2 through the selective oxidation of bulk molybdenum patterns using Joule heating, followed by sulfurization. By passing an electric current through molybdenum patterns under ambient conditions, localized heating induced the formation of a molybdenum oxide layer, primarily MoO2 and MoO3, depending on the applied power and heating duration. These oxides act as nucleation sites for the subsequent growth of MoS2. The properties of the grown MoS2 films were investigated using Raman spectroscopy and photoluminescence measurements, showing promising film quality. This study demonstrates that Joule heating can be an effective method for precise control over TMD growth, offering a scalable approach for producing high-quality 2D materials that have the potential to be integrated into next-generation electrical and optoelectronic technologies.

Enhancement of Joint Properties in B4C/TC4 Connections by adding AlN to AgCuTi brazing materials

ABSTRACT In this study, the surface treatment of boron carbide ceramics was conducted, and an AgCuTi-AlN + AgCu foil composite brazing material system containing aluminum nitride (AlN) particles were employed to connect B4C ceramics and TC4. The addition of 3 wt% AlN improved the structure of the intermediate layer, providing more nucleation sites for solid solution, resulting in a more compact microstructure. However, with an increased AlN content of 6 wt%, the fluidity of the brazing material decreased, leading to a degradation of mechanical properties. When the AgCuTi-3wt%AlN + AgCu foil composite brazing material system was applied for the joining process at 850°C, the highest shear strength obtained was 68 MPa, representing a 70% increase compared to the non-additive condition.

The Preparation of C-S-H Powder Seeds and Their Effect on the Early Hydration Performance of Cement Paste

C-S-H/PCE suspension can boost the hydration degree and strength of cement composite binding. However, the suspension will inevitably precipitate after a period of time, which is not conducive to its preservation, and its low solid content increases transportation costs in practical applications. In this study, utilizing synthetic PCE as a template, C-S-H/PCE suspension was synthesized using a co-precipitation method. Subsequently, powder seeds were produced via the spray-drying technique, and these prepared powder seeds were analyzed via microscopic characterization. The impact of these powder nucleating agents on cement hydration kinetics was evaluated through hydration heat measurements and hydration degree, fluidity, and compressive strength testing. The results indicated that these powder seeds exhibited a nano-film morphology. Their nucleation effect significantly enhanced the cement hydration rate, increased the degree of hydration, and improved strength. The hydration kinetics showed that the hydration of cement mixed with nucleating agents was not governed by a single reaction mechanism, but rather constitutes a complex, multi-component reaction process. As the content of nucleating agents increased, higher dosages of nucleating agents accelerated the production of more products within a short period, causing the system to rapidly transition to phase boundary reaction control. When the dosage of nucleating agents reached 2%, the cement hydration process bypassed the phase boundary reaction control stage and transitioned directly from the crystallization nucleation and crystal growth control process to the diffusion-controlled phase. Although the influence of powder seeds on the enhancement of the early-stage strength of mortar was slightly lower than that of the suspension, the powder was beneficial to its storage and transportation. Therefore, it has the potential to replace the suspension.

Initial Stage Oxidation of 304HCu Stainless Steel in Oxygen Environment

The early stages of oxidation and the development of transient initial oxides on 304HCu stainless steel (SS) were investigated by isothermal oxidation at 650 and 750 °C in a pure oxygen environment using thermogravimetry. At 750 °C, the formation of the continuous oxide layer occurs more rapidly, exhibiting protective parabolic kinetics, where the slow diffusion of iron through the oxide layer governs the oxidation rate. The oxide scales primarily consist of binary oxides of iron and chromium, with noticeable segregation of manganese and niobium in the early stages. Distinct morphological differences were observed in the transient initial oxide scales formed at the two temperatures, each providing additional nucleation sites for oxide formation. The GDOES depth profiles indicated the migration of Cu from the oxide/scale interface to the oxide scale. The role of the oxide composition and its morphology on the oxidation behavior of 304HCu SS are discussed in detail.

High‐Performance PLA Foam Blocks Prepared From Beads Modified by Chain Extension and Heterogeneous Nucleation

ABSTRACTSupercritical CO₂ foaming effectively forms a uniform cellular structure in polylactic acid (PLA) beads by utilizing the high diffusion rate and solubility of CO₂ in polymers. In this study, PLA beads are modified with a chain extender (CE) composed of ethylene and glycidyl methacrylate, while thermoplastic polyurethane (TPU) serves as a heterogeneous nucleating agent. After being foamed with supercritical CO, the modified PLA beads are compression molded into foam blocks. The volume expansion ratio of PLA/TPU/CE foams increases by 12.5‐fold, and the resulting foam blocks exhibit a high compressive modulus of 21 MPa. The enhanced compressive strength results from the synergistic effects of chain extension and heterogeneous nucleation, which enhance the material's cellular structure and internal crosslinking. This study offers an effective strategy to enhance the compressive properties of PLA foam blocks, expanding their applications in high‐performance industries. In addition, the use of eco‐friendly PLA and the potential for scalable production make this approach a promising alternative for sustainable materials.

Deciphering the Evolution of Current Distribution in Hybrid Silver Vanadium Oxide / Carbon Monofluoride Cathodes within Lithium Primary Batteries.

For batteries to function effectively all active material must be accessible requiring both electron and ion transport to each particle. A common approach to generating the needed conductive network is the addition of carbon. An alternative approach is the electrochemically induced formation of conductive reaction products generated with intimate contact to the active material. This study probes silver vanadium oxide (Ag2V4O11, SVO), carbon monofluoride (CFx), and hybrid SVO/CFx electrodes in lithium batteries. Ex situ XRD identifies Ag0 as a reduction product from SVO and LiF from CFx that can be followed as a function of depth-of-discharge (DOD). Spatially-resolved operando energy dispersive x-ray diffraction reveals that presence of SVO alleviates reaction heterogeneity in the electrodes which are electron transfer limited in the absence of sufficient Ag0. Synchrotron X-ray tomography reveals silver particles to be more closely spaced near the current collector indicating multiple nucleation sites for their formation. Finally, enthalpy potentials, determined via operando isothermal microcalorimetry describe the current distribution adding further insight to the discharge process of the two active materials. Taken together, these results provide a comprehensive understanding of hybrid SVO/CFx cathodes and give guidance on optimal compositions that balance power and energy density considerations.

Preparation and Thermal Performance Study of a Novel Organic-Inorganic Eutectic Phase Change Material Based on Sodium Acetate Trihydrate and Polyethylene Glycol for Heat Recovery.

A novel organic-inorganic eutectic phase change material (PCM) based on sodium acetate trihydrate (SAT) and polyethylene glycol (PEG) was developed to meet the needs of heat recovery and building heating. Three kinds of PEG with different molecular weights were selected to form organic-inorganic eutectic PCM with SAT. The thermal properties of three series of SAT-PEG eutectic PCM were compared based on DSC results, focusing on the impact of PEG addition on the phase change temperature and enthalpy of SAT, as well as the melting uniformity. The inhibitory effects of two nucleating agents on the supercooling of SAT-PEG eutectic PCM were systematically investigated. The effect of PEG on the crystallization behavior of SAT was studied using a metallographic microscope. To evaluate the thermal reliability of the SAT-PEG eutectic PCM, 600 cycles of melting-solidification experiments were conducted. Experimental results show that SAT can form eutectic PCMs with PEG200, PEG600, and PEG6000, respectively, with high enthalpy and excellent melting uniformity. The phase change temperature ranged from 55 °C to 60 °C and the enthalpy was as high as 250-280 kJ/kg. The results of the cooling curves show that 10 wt% tetrasodium pyrophosphate decahydrate (TPD) can reduce the supercooling degree to less than 1 °C. Significantly, all three series of SAT-PEG eutectic PCMs exhibit exceptional thermal reliability after 600 cycles of melting-solidification, with shifts in the phase change temperatures and enthalpies of less than 4%. XRD diffraction patterns showed that SAT, PEG, and TPD were physically mixed without a chemical reaction to form new substances. Microscopic images reveal that the addition of PEG preserves the original needle-shaped crystal morphology of SAT while reducing its crystal size. The rapid formation of small crystals can provide more nucleation points and expedite crystallization, thereby enhancing the heat release capabilities of the PCM.

Antimicrobial hydrogel scaffolds from Barba de Viejo microfibers, alginate and ag nanoparticles via green synthesis

Natural fibers are being employed in the development of the next generation of biomaterials, due to their reduced environmental impact and the ease of their functionalization with natural polymers. In this study, Barba del Viejo fibers were treated with NaOH and bonded with alginate through ionic gelation by using CaCℓ2, which facilitates ionic interactions between alginate and Ca2+. Additionally, antimicrobial Barba del Viejo/alginate/silver nanoparticles(BVA/Ago) scaffolds were developed from the NaOH-treated BV-microfibers, silver salt and sodium alginate, with mint leaves extract as a nucleating agent. The functional and crystalline structure of microfibers and the hydrogels developed were analyzed using the FTIR and XRD. SEM explained that the diameter of the NaOH-treated microfibers was ⁓1.32 μm. The morphological images of the hydrogels, confirm the functionalization of alginate with microfibers and the formation of Ago nanoparticles within the hydrogels network. The swelling ratio of the hydrogels increased with alginate functionalization on BV-microfibers, improving NaOH treatment, but decreased the degradation rate. UV-spectra showed absorption peaks in the wavelength range of between 432 and 442 nm, confirming the surface plasmon resonance effect of the Ago nanoparticles within the scaffolds. TEM analysis confirms that the Ago nanoparticles in hydrogels were spherical in shape, with sizes ranging from ⁓2 and 10 nm. The zeta potential analysis indicates that the Ago nanoparticles possess negative charges, providing a stable surface that helps to prevent aggregation and, therefore, demonstrating a homogeneous distribution throughout all the BVA/Ago scaffolds prepared. The antimicrobial studies reveal that the BVA/Ago scaffolds exhibit significant antibacterial activity against E.coli and S.aureus bacteria. Further investigations are affirmed to study the potential applications of these scaffolds in infection-control wound dressing.

Tea polyphenol-loaded chitosan/pectin nanoparticle as a nucleating agent for slurry ice production and its application in preservation of large yellow croaker (Pseudosciaena crocea).

Slurry ice preparation experiences considerable supercooling, which can be mitigated by nano-nucleating agents. A nano-nucleating agent (CH/PE-TP NPs) was prepared by ultrasonication-assistant self-assembly of chitosan (CH) and pectin (PE), encapsulated with tea polyphenols (TP). Ultrasonication for 10 min downsized self-assembled aggregates from 5.4 μm to approximately 500 nm and improved the dispersion of NPs. Optimal encapsulation efficiency was achieved with a CH/PE ratio of 1:5 (v/v), pH 5.0 and a TP concentration of 0.8 mg/mL. FTIR analysis indicated CH and PE encapsulated TP through electrostatic interaction between amino and carboxyl groups. Furthermore, the spherical shape of NPs was captured by electron microscopy. The addition of CH/PE-TP NPs (simulated seawater/NPs 4:6, v/v) for slurry ice production led to a reduction in supercooling by 8.3 °C and decreased energy consumption by 24.8 %. Notably, the CH/PE-TP NPs could be reused by refreezing the melted water of slurry ice. Total volatile basic nitrogen, pH, thiobarbituric acid reactive substances and total viable bacteria count demonstrated that CH/PE-TP NPs-based slurry ice was more effective than flake ice and conventional slurry ice in preserving large yellow croaker. In summary, CH/PE-TP NPs as nucleating agent effectively reduce energy consumption and extend the shelf life of aquatic products.

The effect of graphene nanoplatelets on the aging precipitation behavior and mechanical properties of magnesium matrix composite

Aging can effectively improve the mechanical properties of Mg alloys. The reinforcements can affect the aging kinetics of composites through interaction with the matrix. In this study, the effect of graphene nanoplatelets (GNPs) on the precipitation behavior of Mg-6Zn/GNPs composite was studied. The local region with high GNPs content exhibits a faster aging precipitation rate. Compared with Mg-6Zn alloy, the aging precipitation process of the composites has been accelerated as a whole. It is mainly attributed to the fact that the high density of dislocation near GNPs provides a high-speed channel between nucleation points and atoms for aging precipitation, which promotes aging precipitation. The strengthening effect of the composites mainly results from Orowan strengthening and fine grain strengthening generated by Mg4Zn7 and GNPs, respectively. The existence of GNPs enhances the aging hardening efficiency of the composites to a greater extent than that of the alloy matrix. This work provides a new approach for the design of aging behavior in magnesium matrix composites.

Quantitative features of osteo-bioactive Ti surfaces at the atomic/molecular level.

The osteo-bioactive potential of biomaterials can be modulated by altering material properties such as chemical composition, surface topography, and geometry. The correlation between the physicochemical properties of biomaterials and their osteo-bioactivity is highly complex. As a material widely used in bone repair, the structure-activity/dose-effect relationship between titanium (Ti) surface features and osteo-bioactivity remains unclear. To quantitatively enhance the osteogenic activity of Ti, we employed femtosecond laser (FSL) technology to create Ti surfaces with gradient changes in bioactive (nucleation) sites. Based on the apatite deposition ability on the etched surfaces, the quantitative relationship between the osteo-bioactivity of Ti surfaces and their characteristic parameters was systematically explored. Concurrently, classical molecular dynamics (MD) simulations were utilized to investigate the aggregation behavior of calcium and phosphate ions on the Ti surfaces with different sites. The findings from mineralization experiments revealed that the type and density of bioactive sites could influence the deposition of apatite. It was further identified that TiO2 and Ti-OH are the crucial bioactive sites, with basic Ti-OH exhibiting superior efficacy as a bioactive site compared to its acidic counterpart. Moreover, the bioactive (nucleation) site densities should be maintained at a minimum of 2.33 ± 0.55 nm-2 for TiO2 and 2.50 ± 0.59 nm-2 for -OH, ensuring satisfactory osteo-bioactivity on the Ti surface. The results provide the atomic/molecular features of Ti surfaces that effectively foster apatite deposition and bioactivity, promoting the rapid progression of titanium-based bone repair materials.

Influence of V/B ratio and rolling treatment on the grain refinement efficacy and anti-fading ability of Al-V-B master alloys

As a promising anti Si-poisoning grain refiner, Al-V-B master alloys have gained increasing attention in the past several years. However, the effect of V:B ratio on the grain refinement effect, as well as the refining mechanism has not been clearly investigated. This work investigates the impact of V:B ratio on microstructures of Al-V-B master alloys and grain refinement efficacy for α-Al grains in AlSi alloys. In addition, the effect of rolling treatment on the agglomeration and sedimentation of Al-V-B master alloys has been investigated. It demonstrates that the V:B ratio significantly affects primary secondary phases within Al-V-B master alloys, with an optimal ratio of 2.33 (Al-4.2 V-1.8B) leading to the finest average α-Al grain size of ~98 μm in the Al8Si alloy. Moreover, rolling treatment further enhances the grain refinement efficacy of Al-4.2 V-1.8B master alloy by dispersing VB2 agglomerates/particles and reducing agglomeration and sedimentation during smelting. Accordingly, the rolled Al-4.2 V-1.8B master alloy reduces the average α-Al grain size to ~75 μm at only 50 % amount of the as-cast Al-4.2 V-1.8B master alloy, improving the grain refinement efficacy by 25 % (75 μm v.s. 98 μm). At the same time, the rolled Al-4.2 V-1.8B master alloy exhibits exceptional anti-fading ability, maintaining a stable grain refinement efficacy for up to 120 min. Cs-corrected transmission electron microscopy (TEM) reveals that VB2 particles act as primary nucleation sites for α-Al grains, with a specific crystallographic orientation relationship: [1 1 2¯ 0] (0001) VB2 || [1¯ 1 0] (111) α-Al. This study provides valuable insights into the design of Al-V-B master alloys with superior grain refinement efficacy and anti-fading ability for AlSi alloys.

Variation law of micro-void distribution characteristics in early stage of spallation damage

The development trend of spallation damage mechanics is to construct a physical model that couples information with micro-mesoscale structure of materials, which also promotes the development of numerical calculation methods, experimental techniques and theoretical research. The mechanism responsible for plastic deformation and failure of structural metal materials at high strain rates is complex and ainfluenced by heterogeneities in the micro-mesoscale structure that comprises the distribution of grain boundaries, interfaces, and pre-existing densities voids. The distribution of these mesoscale heterogeneities can provide either strengthening behavior or void nucleation sites and influence spall failure behavior. Due to the lack of evolutionary information of micro-mesoscopic void distribution characteristics, the current spallation damage model is not only restricted in its application in extreme environments with high strain rates, high pressures, and shock, but also does not effectively provide some information about the correlation between material damage and final material fragmentation particle size, which is of very concern in engineering. Therefore, it is urgent to develop a spallation damage model that can reflect the variation law of micro-mesoscopic void distribution characteristics in damaged materials. The probability distribution function of void nucleation based on cosine function is given in this work by analyzing various influencing factors in the process of void nucleation, combining the characteristics of early void growth, and considering the convenience of analytical solution. The analytical calculation results of the new probability function of void nucleation are consistent not only with the results of the variation of void number with time calculated by molecular dynamics, but also with the experimental results of tantalum spallation in the early stage of damage development, that is to say, the new probability function of void nucleation can reflect the variation law of micro-void distribution characteristics in the early stage of spallation damage to a certain extent.

Honeycomb-like Superstructure of 3D Sodiophilic Host for Anode-Free Sodium Batteries

Sodium metal batteries (SMBs) have emerged as a promising candidate for large-scale energy storage systems due to their abundance and cost-effectiveness. However, the high reactivity of sodium (Na) inevitably leads to side reactions and it's infinite volume expansion would definitely limit the applications. The anode-free Na batteries (AFNB) significantly enhance energy density by eliminating excess sodium, but bring a few challenges in terms of cycling stability. In this study, we report that honeycomb-like Bi-nanosheets arrays vertically grown on a Cu mesh, this unique 3D superstructure accommodate the volumetric changes and provides abundant sodiophilic nucleation sites. The Na||Cu half-cell battery demonstrates high reversibility of Na plating/stripping with an average coulombic efficiency (CE) of 99.8% at high current density. The Na||Na symmetrical cell exhibits a stable cycle lifespan of over 1000 hours at a significant discharge depth (DOD) of 75%. The NaTi2(PO4)3 (NTP) cathode in AFNB cell with an N/P ratio of 1 displays an initial capacity of 95.18 mA h g-1 for 267 cycles at 1 C, with an outstanding capacity retention of 93.22%. Our work proposes a potential path toward establishing a highly sodiophilic 3D sodium host, thereby promoting its application in high-stability AFNBs.

Transverse texture weakening and anisotropy improvement of Ti-6Al-4V alloy sheet via asymmetric rolling and static recrystallization annealing

Traditional rolled titanium alloys usually exhibit a distinct transverse texture, which is quite stable in subsequent annealing and leads to anisotropic mechanical behaviors. In this work, Ti-6Al-4V alloy was fabricated by asymmetric rolling and recrystallization annealing. The microstructure, texture, and anisotropy evolution were systematically studied. The results show that the <0001>//ND ± 30° RD texture component is formed during the rolling thinning process under the combined action of compressive stress and shear stress. The corresponding grains and αs prioritize nucleation and grow rapidly during subsequent annealing. The transverse texture are consumed or swallowed up before they grow up. The β phases provide secondary nucleation points for α grains. As a result, grains grown rapidly are decomposed and orientations are further established on adjacent matrix. The grains formed by preferential growth and secondary nucleation show more random orientation, and volume fraction of complete transverse texture decreases from 60.1% to 19.3%. Accordingly, the anisotropy of yield strength and tensile strength is decreased by 181MPa and 195MPa, respectively. The transverse texture is weakened by asymmetric rolling and static recrystallization, which provides an efficient way for producing high-performance rolled titanium alloy in the industry.

Regulated Crystallization Through Intermolecular Interactions Bridging for Efficient Tin‐Based Perovskite Solar Cells

AbstractTin halide perovskite (THP) has emerged as a promising lead‐free material for high‐performance solar cells, attracting significant attention for their potential use for energy conversion. However, the rapid crystallization of THP due to its high Lewis acidity and easy oxidation of Sn2+ leads to poor morphology and rampant defects in the resulting perovskite films. These strongly hamper the advances in efficiency and stability in THP solar cells. Herein, a comprehensive crystallization regulation strategy is demonstrated by introducing methyl carbazate (C2H6N2O2, MeC) to regulate the crystallization kinetics of perovskite through inter‐molecular interactions. The coordination bonds (O…Sn) and hydrogen bonds (N─H…O) between MeC and perovskite bridge the perovskite lattice together, helping suppress the oxidation of Sn2+, meanwhile, restraining the fast crystallization of perovskite in the precursor solution, by enhancing nucleation sites. More importantly, the connection by MeC can reduce the deep‐level trap state defect density, significantly restraining non‐radiative recombination and improving the carrier lifetime. Consequently, this facile strategy offers valuable insights into THP crystallization kinetics and allows an enhanced high power conversion efficiency from 10.43% to 14.02% to be achieved with good stability.

Insights into the Assembly of Peptides Catalyzed by Polysaccharides.

Nucleation is a critical step that determines the assembly pathway and the structure and functions of the peptide assemblies. However, the dynamic evolution of interactions between nucleating agents and peptides, as well as between peptides themselves during the nucleation process, remains elusive. Herein, we show that the heterogeneous nucleating agent carboxymethylcellulose (CMC) can promote the nucleation of Aβ16-20 (KF) peptide. The Förster resonance energy transfer (FRET) technology was used to unveil the interaction dynamics between the CMC and KF peptide. Initially, CMC enriches KF monomers through weak nondirectional electrostatic interactions. The electrostatic screening reduces the electrostatic repulsion between KF molecules. Subsequently, KF-KF interactions become dominant, leading to the dissociation of KF from the CMC and nucleation. By adjustment of the adding time, dosage, size, and active sites of CMC, the assembly kinetics of KF can be effectively controlled. This study helps gain a deep understanding of the early heterogeneous nucleation process of peptide assembly and provides valuable guidance for the rational design of efficient nucleating agents for peptide assembly toward functional materials.

Stabilizing Polyoxometalate for Enhanced OER Performance Using a Porous Manganese Oxide Support.

The oxygen evolution reaction (OER) is a critical challenge in electrocatalytic water splitting, hindered by high energy demands and slow kinetics. Polyoxometalates (POMs), recognized for their unique redox capabilities, structural archetypes, and molecular precision, are promising candidates for the oxygen evolution reaction (OER). Yet, their application is hindered by high water solubility, causing rapid degradation and efficiency loss under harsh OER conditions. This study enhances the performance and stability of polyoxometalates (POMs) for OER by anchoring keggin-type POM [TiCoW11O40]7- nanosheets onto a conductive, carbon-protected manganese oxide (C-Mn2O3) nanospheres support. The acquired porous framework enhances POM/C-Mn2O3 (PCM) contact, improving stability, reaction kinetics, and redox activity by offering nucleation sites, electronic pathways, and abundant active sites, significantly boosting OER activity. The resulting PCM nanohybrid demonstrates remarkable OER activity in 1M KOH, requiring only a 300 mV overpotential to achieve a current density of 10 mA cm-2 with a Tafel slope of 88 mV/dec. The PCM electrocatalyst also shows high mass activity (784 A/g at 1.6 V) and maintains stability over 100 hours at 100 mA cm-2 without performance fatigue. Consequently, this study offers a viable strategy for developing efficient, durable electrocatalysts using low-cost materials.

Hydrate-Based Methane Storage in Biodegradable Hydrogels Absorbing Dilute Sodium P-Styrenesulfonate Solution

Developing an exceptional reaction medium with high promotion efficiency, desirable biodegradability and good recyclability is necessary for hydrate-based methane storage. In this work, a kind of eco-friendly hydrogel, polyvinyl alcohol-co-acrylic acid (PVA-co-PAA), was utilized to absorb dilute sodium p-styrenesulfonate (SS) solution, for constructing a hybrid reaction medium for methane hydrate formation. Hydrogels or dilute SS solutions (1–4 mmol L−1) had weak or even no promoting effects on hydrate formation kinetics, while the combination of them could synergistically promote methane hydrate formation. In hydrogel-SS hybrid media containing 1, 2, 3 and 4 mmol L−1 of SS solutions, the storage capacity reached 121.2 ± 1.6, 121.5 ± 3.1, 122.6 ± 1.9 and 120.6 ± 1.6 v/v, respectively. In this binary reaction system, the large surface area of hydrogels provided hydrate formation with sufficient nucleation sites and an enlarged gas–liquid interface, and in the meantime, the dilute SS solution produced an adequate capillary effect, which together enhanced mass transfer and accelerated hydrate formation kinetics. Additionally, the hybrid medium could relieve wall-climbing hydrate growth and improve poor hydrate compactness resulting from the bulk SS promoter. Moreover, the hybrid medium exhibited a preferable recyclability and could be reused at least 10 times. Therefore, the hydrogel-SS hybrid medium can serve as an effective and eco-friendly packing medium for methane hydrate storage tanks, which holds great application potential in hydrate-based methane storage technology.

Optimization of the Zinc Deposition Interface by Sn Nanoparticles for Fast-Charging Zinc Metal Anodes.

The electrodeposition behavior of zinc metal anodes critically correlates with the electrode surface properties. The tendency for inhomogeneous deposition of zinc is more severe, especially under high current density. Herein, the surface structure of zinc and zinc deposition substrates is reconstructed with a uniform metal tin (Sn) coating via a simple evaporation method. Sn nanoparticles can serve on metal nuclei to reduce the Zn nucleation barrier and enable more nucleation sites for even deposition. Moreover, the mechanical stability of the electrode surface is improved via Zn-Sn alloying. Consequently, the uniform Zn deposition/dissolution behavior on Sn-modified two- and three-dimensional copper substrates is reflected in the stable Coulombic efficiency and reduced polarization. The Sn@Zn electrode is endowed with superior stability at a high current density (800 h at 20 mA cm-2). More encouragingly, the full cell installed with a carbon nanotube/MnO2 cathode maintains enduring stability (700 cycles) at 1 A g-1. This work enlightens metal alloy as an effective and instructive modification strategy toward stabilized zinc anodes.