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• High-purity MAPb 0.5 Sn 0.5 I 3 perovskite film without a low-conductivity halide layer was successfully prepared by a two-step solution method. • Porous iodide layers were prepared and can be adjusted by the concentration of the ascorbic acid additive. • Ascorbic acid additives inhibit the oxidation of Sn2+ and act as a chelating agent to control the crystal growth of Pb-Sn mixed perovskites. • The final hole-free photodetector achieves a high responsivity of 0.276 A W−1 and a large specific detectivity of 2.38 × 1012 Jones. Tin (Sn)-lead (Pb) mixed halide perovskites have attracted widespread interest due to their wider response wavelength and lower toxicity than lead halide perovskites. Among the preparation methods, the two-step method more easily controls the crystallization rate and is suitable for preparing large-area perovskite devices. However, the residual low-conductivity iodide layer in the two-step method can affect carrier transport and device stability, and the different crystallization rates of Sn- and Pb-based perovskites may result in poor film quality. Therefore, Sn-Pb mixed perovskites are mainly prepared by a one-step method. Herein, a MAPb 0.5 Sn 0.5 I 3 -based self-powered photodetector without a hole transport layer is fabricated by a two-step method. By adjusting the concentration of the ascorbic acid (AA) additive, the final perovskite film exhibited a pure phase without residues, and the optimal device exhibited a high responsivity (0.276 A W−1), large specific detectivity (2.38 × 1012 Jones), and enhanced stability. This enhancement is mainly attributed to the inhibition of Sn2+ oxidation, the control of crystal growth, and the sufficient reaction between organic ammonium salts and bottom halides due to the AA-induced pore structure. [Display omitted] [ABSTRACT FROM AUTHOR]

• New potential optimized ion charge predicts high temperature behavior of SrTiO 3. • SrTiO 3 melting point simulated by new potential (2403 K vs. experimental value of 2333 K). • Rapid cooling reveals prevalence of six-fold coordination amorphous ordering in SrTiO 3. • New kinetic two-phase growth method controls melt cooling rate to form crystals. The functional properties of ABO 3 -type perovskite materials have garnered extensive attention, yet their solidification properties have remained challenging to investigate due to high-temperature environments and characterization limitations. In this study, molecular dynamics simulations are employed to comprehensively explore the melting, quenching, and crystal growth processes of SrTiO 3 (STO) structural evolution. Through iterative fitting and optimization of ion effective charge, a set of potential functions capable of accurately simulating the high-temperature melting of STO are derived. The melting point obtained for STO (2403 K) using the two-phase coexistence method closely corresponds to the empirical value (2333 K), affirming the precision of the optimized potential. Quenching the molten STO yields an amorphous structure characterized primarily by Ti-O six-fold coordination, which increased by 13.09% when reduced to 300 K at a cooling rate of 0.1 K/ps. Notably, the results for different cooling rates revealed that slower cooling rates and lower temperatures yielded more ordered amorphous structures. To circumvent the formation of amorphous states during crystal growth of perovskite materials, we have developed a kinetic two-phase growth (KTPG) method. This approach regulates the cooling rate within a solid-liquid two-phase system, maintaining constant low supercooling at the interface to mimic STO crystal growth kinetics. Cooling at 0.01 K/ps to 1760 K leads to a notable transformation, with the percentage of Ti-O six-fold coordination reaching 90%. This signifies substantial progress in achieving crystal growth through this method, highlighting its efficacy in facilitating crystal formation from the melt phase. : [Display omitted] [ABSTRACT FROM AUTHOR]

• A novel Al-Containing multi-component boride (MMB 2) was efficiently prepared. • The corresponding in-situ reaction process and growth mechanism are proposed. • The Al-Containing MMB 2 exhibits ultra-high hardness and improved toughness. • The Al-Containing MMB 2 shows superior oxidation activation energy. Multi-component transition group metal borides (MMB 2) have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics. Most of the current methods, however, are complicated and time-consuming, the mass production remains a challenge. Herein, we proposed a new high-efficiency strategy for synthesis of MMB 2 using molten aluminum as the medium for the first time. The prepared Al-containing multi-component borides (TiZrHfNbTa)B 2 microcrystals had a homogeneous composition with a hexagonal AlB 2 structure and ultra-high hardness value of ∼35.3 GPa, which was much higher than data reported in the literature and the rule of mixture estimations. Furthermore, combined with the First-principles calculation results, we found that the Poisson's ratio (v) values exhibit a clearly ascending trend from 0.17 at VEC = 3.5 to 0.18 at VEC = 3.4, then to 0.201 at VEC = 3.2 with the increasing of Al content. This indicates that the intrinsic toughness of multi-component boride microcrystals is obviously enhanced by the trace-doped Al elements. Besides, the fabricated Al-containing multi-component boride microcrystals have superior oxidation activation energy and structural stability. The enhanced oxidation resistance is mainly attributed to the formation of a protective Al 2 O 3 oxide layer and the lattice distortion, both of which lead to sluggish diffusion of O 2. These findings propose a new unexplored avenue for the fabrication of MMB 2 materials with superior comprehensive performance including ultra-hardness and intrinsically improved thermo-mechanical properties. [Display omitted] [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries represent a promising energy storage system with the potential to replace traditional lithium-ion batteries. Recent research has explored the practical applications of Li–S batteries. However, due to the insulation properties of the sulfur components and the shuttle effect of polysulfides, the practical application of Li–S batteries is hindered by poor cycle stability and short life. In this study, we developed a controllable three-dimensional Ti 3 C 2 structure design process, and through in situ growth of TiO 2 nanocrystals, we prepared three-dimensional porous materials with TiO 2 @Ti 3 C 2 heterostructures. These materials constructed using two-dimensional lamellar Ti 3 C 2 function as a conductive skeleton to improve the conductivity of the sulfur cathodes, and through the in-situ growth of nano-TiO 2 to introduce more binding sites and provide more chemisorption sites to limit the dissolution and shuttle of polysulfides. In addition, the TiO 2 @Ti 3 C 2 heterointerface generated in situ on the surface of the lamellar structure can induce an internal electric field and increase active reaction sites, which promotes reaction kinetics, accelerates charge diffusion/transport, and promotes LiPS transformation. The materials designed in this study can effectively restrain the shuttle effect by realising the association process of adsorption, capture, and transformation of polysulfides. Thus, when applied as the sulfur cathode frame, it shows a high specific capacity of 1261.41 mAh g−1 at a rate of 0.1 C. In addition, a specific capacity of 66.5 % is maintained over 500 cycles at a rate of 1 C. This strategy supports the development of Li–S batteries with extraordinary performance and opens up a promising way to design next-generation electrochemical energy storage devices. [Display omitted] [ABSTRACT FROM AUTHOR]

• In 6xxx series alloys, the alleviation degree of microsegregation is distinct for different alloying elements, sequenced as Mg > Si > Fe, when cooling rate increases from 5 K/s to 128 K/s. • The different solute elements impose its own response of partitioning to cooling rate, denoted as R k. A theoretical equation of R k is proposed, which is a function of equilibrium partitioning coefficient, crystal growth rate, and diffusion coefficient of solute in liquid. • A broad range of R k values of other common solute elements in Al alloys are evaluated, delivering a handy tool to describe microsegregation behavior. It is commonly recognized that the cooling rate has a substantial effect on solute partitioning and its resultant microsegregation during solidification. The classical dendrite tip undercooling theory clarifies the mitigation of microsegregation by increasing the cooling rate. However, most of the studies focused on binary alloys, leaving an open question as to whether the microsegregation of different solutes in a multi-component alloy system exhibits a relieving degree similar to increasing cooling rate. Taking a widely used 6022-type Al alloy (Al-0.76Mg-0.93Si-0.2Fe) as a model alloy, the current study reveals that the microsegregation of Mg gets alleviated to the greatest extent, followed by those of Si and Fe when the cooling rate increases from 5 to 128 K/s. This phenomenon is attributed to the solute-based difference in response to partitioning to cooling rate (denoted as R k). We propose a theoretical equation to quantify R k , and the R k values of solute Mg, Si, and Fe successfully explain the rank of solute partitioning in experiments. Furthermore, a broad range of R k values of other commonly used alloying elements in Al alloys were calculated and ranked, delivering a handy tool to predict the microsegregation behavior and solubility of different solute elements upon sub-rapid solidification, which is consistent with experimental observation. This framework can also be extended to other multi-component alloy systems. [ABSTRACT FROM AUTHOR]

• The ETEs additions improve thermal stability of the rapid solidified alloys. • Adding ETEs inhibit the formation of α-Fe crystals during rapid solidification. • Slightly rises in δ and negative Δ H mix coarsen the crystals in annealed alloys. • Excessive high δ and negative Δ H mix refine the crystals on the contrary. • The variation in crystal size results from the combined action of rapidly decline in competitive growth and slowly enhancement in diffusion inhibition effect during nanocrystallization. Unique rapid solidified structure and nanocrystallization mechanism enable the Fe-based nanocrystalline alloys with high Cu content excellent soft magnetic properties and good manufacturability, and also results in unusual phenomena in terms of alloying effects. In the present work, we systematically studied the influence rules of early transition elements on the rapid solidified structure and nanocrystallization behaviors of Fe-Si-B-Cu soft magnetic alloys with high Cu content and explored the related mechanisms. In terms of rapid solidified structure, the additions of early transition elements always inhibit the formation of pre-existing α-Fe crystals even eliminate them, and the additions that could produce larger atomic mismatch parameter (δ) and negative mixing enthalpy (Δ H mix) show stronger effects. In terms of nanocrystallization behaviors, the increases in δ and negative Δ H mix weaken the competitive growth between the pre-existing nanocrystals during annealing and then coarsen the nanostructure of the annealed alloys and deteriorate their magnetic softness, while the excessive increases in δ and negative Δ H mix could significantly suppress the growth of α-Fe crystals by diffusion inhibition during annealing and thus remarkable refine the nanostructure of the annealed alloys and improve their magnetic softness. [ABSTRACT FROM AUTHOR]

[Display omitted] • The steric hindrance effect can effectively modify the particle size of NaA zeolite. • The grain size of NaA-CyOH zeolite is only 776 nm. • The specific surface area of NaA-CyOH can be increased to 85.99 m2/g from 35.24 m2/g. • NaA-CyOH has an excellent regeneration ability. The incorporation of steric effects into the hydrothermal synthesis system of NaA zeolite proves to be an effective method for modifying grain size, enhancing grain dispersion and obtaining single crystal products. In this study, three different molecular configurations, namely short-chain ethanolamine (MEA), long-chain polyethylene glycol (PEG), and ring-chain cyclohexanol (CyOH), were employed to investigate the impact of steric effects on the crystal growth of NaA zeolite. The crystal form, morphology, and particle size of NaA zeolite were characterized using XRD, FT-IR, and SEM techniques. The order of steric hindrance in terms of molecular configuration was found to be as follows: CyOH > PEG > MEA. NaA-CyOH exhibited a high dispersion of single crystal particles, the smallest grain size, and the largest specific surface area and pore volume. To evaluate the ammonium ion adsorption performance, NaA-CyOH-31, the zeolite with the best performance, was utilized for studying the reaction kinetics. The results indicated that the adsorption behavior of NaA zeolite towards ammonium ion could be better described by the quasi second-order equation and the Langmuir model. Furthermore, the evaluation of the regeneration ability of NaA-CyOH zeolite demonstrated that the recovered adsorbent still maintained a high level of adsorption performance. [ABSTRACT FROM AUTHOR]

• Mild and Controllable Fabrication of crystalline Ga 2 O 3 nanostructures. • Kilogram-scale Output of the Ga 2 O 3 nanostructures. • Deep Insight on Growth Mechanism of the Ga 2 O 3 nanostructures. • Interesting Device Applications of the Ga 2 O 3 nanostructures. Currently, the synthesis of nanostructures still encounters two grand challenges: one is the often-required high temperatures and/or high pressures, and the other is the scalable fabrication. Here, to break through such bottlenecks, we demonstrate an ambient-condition strategy for rapid mass production of fourth-generation semiconductor Ga 2 O 3 nanoarchitectures assembled by single-crystalline nanosheets in a controlled manner based on sonochemistry. Their growth is fundamentally determined by the introduced ethanediamine in rationally designed source materials, which could not only protect the metal Ga against reacting with H 2 O into GaOOH, but facilitate the reaction of Ga with OH· radicals for target crystalline Ga 2 O 3 nanostructures. As a proof of concept for applications, the as-fabricated Ga 2 O 3 nanoarchitectures exhibit superb performances for electromagnetic wave absorption with a reflection loss value of 52.2 dB at 8.1 GHz, and ammonia sensing with high sensitivity and selectivity at room temperature, representing their bright future to be commercially applied in modern devices. [Display omitted] A sonochemistry strategy was reported for mass production of crystalline γ-Ga 2 O 3 nanoarchitectures under ambient condition with a high yield of 88% and kilogram-scale output in a controlled manner, excluding the assistance of externally applied high temperatures and high pressures as often-required in reported works. The as-synthesized Ga 2 O 3 nanoarchitectures exhibit superb performances for electromagnetic wave absorption and ammonia sensing with high sensitivity and selectivity at room temperature. The present work could be a significant progress in materials science and technology, to enable the rapid and scalable production of crystalline nanostructures under mild conditions toward practical applications. [ABSTRACT FROM AUTHOR]

Researchers from Inner Mongolia University of Technology conducted a study on the crystal growth of hydrated calcium silicate synthesized from fly ash and lime milk at 100 degrees Celsius. The research focused on incorporating amorphous silica from fly ash and lime milk into microporous calcium silicate powders through dynamic hydrothermal synthesis. Results showed the formation of microporous calcium silicate from an amorphous gel into a crystalline form, with diverse calcium silicate minerals and particle sizes between 10 and 20 micrometers. The study was funded by various organizations and has been peer-reviewed. [Extracted from the article]

Researchers at Nanjing Tech University in Jiangsu, China, have developed a method to enhance the efficiency of hybrid halide perovskite films for various applications, particularly in light-emitting diodes (LEDs). By using a thermally polymerized additive called N-vinyl-2-pyrrolidone (NVP), they were able to control the crystallization and orientation of the perovskite films, resulting in brighter and more stable green luminance in the LEDs. This study sheds light on how to manipulate the crystallization behavior of mixed organo-metal perovskite films, offering valuable insights for future research in this field. [Extracted from the article]

Researchers at Sri Sivasubramaniya Nadar College of Engineering in Tamil Nadu, India, have grown a single crystal of Triethylenediaminium Hydronium Trinitrate (TEDHT) using the slow evaporation solution technique. The crystal was found to have a trigonal crystal system and space group P 3 1 c, with a sharp cutoff wavelength around 320 nm and transparency in the UV region. The study also investigated the thermal stability, photoconductivity, dielectric properties, mechanical stability, and nonlinear optical susceptibility of the TEDHT crystal. This research provides valuable insights for optoelectronic applications and has been peer-reviewed. [Extracted from the article]

Researchers at Anhui Xinhua University in Hefei, People's Republic of China, conducted a study on the role of BPO4 flux in crystal growth, focusing on BaBPO5 crystals. Through high-temperature Raman spectroscopy, they found that PBO7 groups are crucial for crystal growth and remain stable at high temperatures. The addition of PBO4 flux aids in the formation of these PBO7 units, providing insights into crystal growth mechanisms. This peer-reviewed research expands understanding of crystal growth processes and may have implications for other systems. [Extracted from the article]

Researchers at Sun Yat-sen University in Guangzhou, China, have conducted a study on the early stages of polymer crystallization driven by surface wrinkling and compressive stress in thin films. Using atomic force microscopy and X-ray scattering measurements, they found that surface wrinkling precedes nucleation and crystal growth, potentially reducing the nucleation barrier. This research sheds light on the role of localized structural inhomogeneity in the formation of crystalline supramolecular structures, providing new insights into the process. The study was funded by the National Natural Science Foundation of China and the National Key Research & Development Program of China, and has been peer-reviewed. [Extracted from the article]

Researchers at Xinjiang University have conducted a study on the inhibition of the growth rate of ZnS anode crystal plane to enhance photocatalytic hydrogen production performance. The research focused on the impact of surfactants on the particle size of photocatalysts and found that anionic surfactants can reduce the catalyst size, leading to optimal performance for hydrogen production. This investigation offers new insights into synthesizing small-size and high-performance photocatalysts, contributing to advancements in nanotechnology and emerging technologies. The study was funded by various organizations and has been peer-reviewed, providing valuable information for further research in the field. [Extracted from the article]

Researchers at Tianjin University in China have conducted a study on the growth and morphology of flaky crystals using benzanilide as a model material. The study explores the mechanisms of crystal growth, surface structure, solvent diffusion, and solvent-interface interactions. The research provides insights into the solvent effect on crystal morphology and offers guidance for optimizing crystallization conditions to obtain shape-tailored crystal products. This study has been peer-reviewed and can contribute to a deeper understanding of crystal growth processes. [Extracted from the article]

Researchers at Zhejiang University have made significant advancements in crystal growth with nanoparticles, achieving continuous 1D growth with high aspect ratios through oriented aggregation of dendrites. This innovative approach allows for the creation of mono-crystalline dendrite branches with ultra-high aspect ratios and uniform characteristics. The findings suggest potential applications for high aspect ratio nanowires and offer insights into general 1D crystal growth systems. The study was published in Communications Materials by Nature Portfolio, and more information can be obtained from the lead author, Quan Wan, at Zhejiang University. [Extracted from the article]

Researchers at Nanjing University of Posts and Telecommunications in Jiangsu, China, have reported on the potential of cubic boron arsenide (c-BAs) for addressing heat dissipation challenges in modern electronics. The material's high thermal conductivity and ambipolar mobility make it suitable for electronic devices and thermal management applications. The study highlights the need for further research in large-scale synthesis and physical property tuning of c-BAs, focusing on future thin-film epitaxy techniques. This peer-reviewed research provides insights into the design considerations for the future development of c-BAs thin-films. [Extracted from the article]

Researchers at Tianjin University in China have developed a novel method called multi-stage cascade batch reactive-heating crystallization to produce non-agglomerated lithium carbonate crystals. This process aims to decouple nucleation and crystal growth, resulting in crystals with regular morphology and improved process yield. The study, supported by the National Natural Science Foundation of China and the Natural Science Foundation of Tianjin, highlights the advantages of this new approach in synthesizing micrometer-sized non-agglomerated crystals. The research, published in Chemical Engineering Science, emphasizes the importance of mathematical modeling and experimental validation in optimizing the crystallization process. [Extracted from the article]

A recent report from the Chinese Academy of Sciences discusses advancements in the field of Chemicals and Chemistry, specifically focusing on noncentrosymmetric molybdenum/tungsten tellurites for second-order nonlinear optical (NLO) materials. These compounds show promise for optoelectronic technologies in the mid-infrared range, with unique properties such as high optical transmittance and wider band gaps compared to conventional NLO materials. The research aims to enhance the understanding of these materials and accelerate the development of high-performance mid-IR NLO crystals to meet technological demands. [Extracted from the article]

A patent was issued for a high-energy laser apparatus for thin film temperature sensing by Raytheon Company. The invention involves a high-energy laser element with a non-conductive substrate layer assembly, a reflector layer assembly, and a thermally conductive carbon layer. The patent details the structure and components of the high-energy laser element, emphasizing the use of thermally conductive carbon layers for improved performance in tactical environments. The patent provides a method for assembling the high-energy laser element, including steps such as forming the non-conductive substrate layer assembly and growing the thermally conductive carbon layer. [Extracted from the article]

Researchers from Delft University of Technology conducted a study on the crystal growth of calcium oxalate under laminar flow conditions in a microfluidic device, simulating kidney stone formation. The study focused on the impact of fluid flow rate, molar ratio of calcium to oxalate, and the presence of an organic protein, osteopontin, on crystal growth. The research found that altering the molar ratio of calcium to oxalate significantly affected the growth rate of the crystals, with different pseudopolymorphs nucleating based on the ratio. The study concluded that calcium oxalate dihydrate was observed under all conditions, while calcium oxalate monohydrate was seen in experiments with specific molar ratio values. [Extracted from the article]

Researchers from Tianjin University of Science and Technology in China have developed a new antibacterial material, ZIF-8@ZIF-67, which shows effectiveness against both Gram-positive and Gram-negative bacteria. By combining graphene oxide (GO) with ZIF-8@ZIF-67, the researchers were able to enhance the antibacterial properties of the material, achieving high inhibitory rates against E. coli and S. aureus. This research, supported by the National Natural Science Foundation of China, highlights the potential of graphene oxide supported crystal growth for improved antibacterial performance. [Extracted from the article]

A study from China University of Geosciences explores the formation and alteration mechanisms of titanium minerals in volcanic sedimentary sequences, crucial for understanding the Ti element cycle on Earth. Using advanced characterization techniques, the research reveals that the growth of TiO2 nanoparticles in volcanic ash is regulated by Ostwald ripening and oriented attachment mechanisms. The study highlights the sensitivity of TiO2 nanoparticles' growth behaviors to microenvironments and the formation of large brookite crystals during the alteration process of unstable Ti minerals. This research provides valuable insights into nanoscale weathering processes and crystal growth mechanisms in altered volcanic ash. [Extracted from the article]

A recent report from Tianjin University of Technology discusses advancements in the direct nitridation method for growing aluminum nitride (AlN) crystals, a wide-bandgap semiconductor. The study highlights the environmentally friendly and cost-effective nature of the direct nitridation method, which shows promise for industrial production. Researchers emphasize the importance of controlling various factors such as temperature, dopant type, gas composition, and flow velocity to enhance the growth rate and quality of AlN crystals. This research provides valuable insights for further studies on wide-bandgap semiconductors. [Extracted from the article]

Researchers from Kunming University of Science and Technology in China have published a study on the properties and growth of silicon carbide (SiC) crystals, a third-generation semiconductor with high thermal conductivity and other desirable characteristics. The study focuses on utilizing silicon cutting waste (SCW) from silicon wafer production to prepare SiC materials, aiming to reduce waste and environmental pollution. The research highlights the principles, methods, and properties of SiC growth, crystal structure, and the application of SiC prepared from SCW. For more information, the full article is available in the Journal of Materials Research and Technology. [Extracted from the article]

Recent research from Technical University Munich (TU Munich) explores the impact of solvent additives on the morphology and formation kinetics of organic solar cells. The study investigates two solvent additives, 1-chloronaphthalene and tetralin, and their selectivity for different components in the solar cells. The findings suggest that solvent additives can promote phase separation and crystal growth, ultimately enhancing the power conversion efficiency of the solar cells. This peer-reviewed research sheds light on the potential for optimizing solar cell performance through solvent manipulation. [Extracted from the article]

Researchers from the University of Pardubice in the Czech Republic conducted a study on the structural relaxation and crystal growth kinetics of amorphous nifedipine using differential scanning calorimetry and Raman microscopy. The research found that nifedipine exhibited complex crystallization processes and was prone to rapid glass-crystal growth below the glass transition temperature. The study also highlighted the correlation between structural relaxation and crystal growth, suggesting a threshold in the complexity of cooperating regions that could impact the rate of crystal growth. This research was funded by the Ministry of Education, Youth And Sports of The Czech Republic and published in the journal Molecules. [Extracted from the article]