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This report (I) aims to investigate defect behavior during the growth of heavily phosphorus (P)-doped Czochralski silicon (HP-Cz-Si) crystals. The defects and P chemical states in as-grown crystals with a resistivity of 0.6 mΩ cm and the wafers annealed at around 600 °C were evaluated by transmission electron microscopy and hard x-ray electron spectroscopy (HAXPES). Micro-dislocation loops (MDLs) were observed in the bottom portion of the crystal, and larger stacking faults (SFs), including complex dislocation clusters, were observed in the middle portion. HAXPES revealed two different P states, P1 and P2. P1 was attributed to a substitutional P (Ps). The P2 present in as-grown crystals was found to be electrically active, while the newly formed P2 after annealing was electrically inactive, indicating that they are in different states. HAXPES evaluation of HP-Cz-Si after electron irradiation showed similar behavior to P2 after annealing, suggesting that P-vacancy (V) clusters are formed when the crystals are held at temperatures below 600 °C during crystal growth. Combining the experimental results with our theoretical analysis in the report (II) based on density functional theory calculations, we identified the following defect formation mechanisms. Interstitial P (Pi) atoms introduced at the melting point become supersaturated during cooling to 600 °C, and MDLs are generated by the aggregation of Si self-interstitials (Is) released through a position exchange from Pi to Ps. In crystal portions with a long residence time below 600 °C, supersaturated Ps transforms into P–V clusters, and Is generated simultaneously are absorbed by the MDLs, which grow into SFs containing dislocation clusters. [ABSTRACT FROM AUTHOR]

Recent studies including our own report (I) have revealed that heavily phosphorus (P) doped Czochralski-silicon (HP-Cz-Si) exhibits peculiar defect behaviors during crystal growth. HP-Cz-Si crystals with a low resistivity of around 0.6 mΩ cm (P concentration of 1.3 × 1020 P cm−3) have interstitial-type stacking faults (SFs) and dislocations, which degrade device characteristics. The purpose of this paper is to clarify what causes the defect behavior in HP-Cz-Si through theoretical calculations. The thermal equilibrium concentrations of substitutional P (Ps), interstitial P (Pi), and (Ps)n-vacancy (V) clusters (n = 1−4) were determined by using density functional theory (DFT) calculations. The concentrations of Pi ([Pi]) and (Ps)nV ([(Ps)nV]) balanced with the given Ps concentration ([Ps]) were obtained as a function of the total P concentration ([P]) and the temperature. On the basis of the calculated results those can quantitatively explain our experimental results in the report (I), we propose a defect model that accurately represents HP-Cz-Si crystal growth. The main feature of the model is that the incorporated Pi atoms at the solid/liquid interface around [Pi] = 1017 Pi cm−3 cause the formation of SFs and dislocations during the HP-Cz-Si crystal growth with around [P] = 1020 P cm−3. Furthermore, DFT calculations were performed for Pi segregation on the SF and for the photoelectron spectra of P 1s measured by hard x-ray photoelectron spectroscopy to explain the other experimental results in the report (I). [ABSTRACT FROM AUTHOR]

Crystal surfaces play a pivotal role in governing various significant processes, such as adsorption, nucleation, wetting, friction, and wear. A fundamental property that influences these processes is the surface free energy, γ. We have directly calculated γ(T) for low-index faces of Lennard-Jones (LJ), germanium, and silicon crystals along their sublimation lines using the computational cleavage technique. Our calculations agree well with experimental values for Si(111) and Ge(111), highlighting the accuracy of the method and models used. For LJ crystals, we identified a premelting onset at Tpm = 0.75Tm, marked by a sharp increase in atom mobility within the second outermost surface layer. Notably, Tpm closely aligned with the endpoint of the LJ melting line at negative pressures, Tend = 0.76Tm. We hypothesize that the emergence and coexistence of a liquid film atop the LJ crystal at Tpm < T < Tm correspond to the metastable melting line under negative pressures experienced by stretched crystal surfaces. Furthermore, our study of thin LJ crystal slabs reveals that premelting-induced failure leads to recrystallization below the homogeneous freezing limit, offering a promising avenue to explore crystal nucleation and growth at extremely deep supercoolings. Finally, no evidence of premelting was detected in the model crystals of Ge and Si, which is consistent with the experimental observations. Overall, our findings offer valuable insights into crystal surface phenomena at the atomic scale. [ABSTRACT FROM AUTHOR]

Advances in cryobiology techniques commonly target either the cooling or the warming cycle, while little thought has been given to ≪repair≫ protocols applicable during cold storage. In particular, crystallization is the dominant threat to cryopreserved samples but proceeds from small nuclei that are innocuous if further growth is forestalled. To this end, we propose a laser editing technique that locally heats individual crystals above their melting point by a focused nanosecond pulse, followed by amorphization during rapid resolidification. As a reference, we first apply the approach to ice crystals in cryoprotected solution and use Raman confocal mapping to study the deactivation of crystalline order. Then, we examine dimethyl sulfoxide trihydrate crystals that can germinate at low temperatures in maximally freeze concentrated regions, as commonly produced by equilibrium cooling protocols. We show how to uniquely identify this phase from Raman spectra and evidence retarded growth of laser-edited crystals during warming. [ABSTRACT FROM AUTHOR]

III-nitrides have fomented a revolution in the lighting industry and are poised to make a huge impact in the field of power electronics. In the III-nitride family, the crystal growth and use of hexagonal BN (h-BN) as an ultrawide bandgap (UWBG) semiconductor are much less developed. Bulk crystals of h-BN produced by the high-temperature/high-pressure and the metal flux solution methods possess very high crystalline and optical qualities but are impractical to serve as substrates or for device implementation as their sizes are typically in millimeters. The development of crystal growth technologies for producing thick epitaxial films (or quasi-bulk or semi-bulk crystals) in large wafer sizes with high crystalline quality is a prerequisite for utilizing h-BN as an UWBG electronic material. Compared to traditional III-nitrides, BN has another unique application as solid-state neutron detectors, which however, also require the development of quasi-bulk crystals to provide high detection efficiencies because the theoretical efficiency (ηi) relates to the detector thickness (d) by η i = 1 − e − d λ , where λ denotes the thermal neutron absorption length which is 47 μm (237 μm) for 10B-enriched (natural) h-BN. We provide an overview and recent progress toward the development of h-BN quasi-bulk crystals via hydride vapor phase epitaxy (HVPE) growth and the attainment of thermal neutron detectors based on 100 μm thick 10B-enriched h-BN with a record efficiency of 60%. The thermal neutron detection efficiency was shown to enhance at elevated temperatures. Benchmarking the crystalline and optical qualities of h-BN quasi-bulk crystals with the state-of-the-art mm-sized bulk crystal flakes and 0.5 μm thick epitaxial films identified that reducing the density of native defects such as vacancies remains the most critical task for h-BN quasi-bulk crystal growth by HVPE. [ABSTRACT FROM AUTHOR]

Two-dimensional colloidal crystals assembled from polystyrene nanospheres have emerged as a pivotal foundation for fabricating large-area nano-functional surfaces. These assemblies, defined by their hexagonal close-packed configuration and interlaced with grain boundaries, have garnered significant attention for applications in plasmonic structures, catalysts, photonic crystals, and inverse opals. Nonetheless, achieving consistent large-scale regularity has proven challenging due to unpredictable crystal growth and the introduction of defects. Utilizing acoustic waves excited from the airside, our experiments demonstrate the significant effects of such waves on the self-assembly process, leading to larger crystal domains and reduced defects. In comparison to the extensively studied water-end excitation techniques, our air-end excitation method introduces a novel dynamic in regulating colloidal monolayer crystallization and presents a comprehensive analysis of varying acoustic parameters, frequency, amplitude, and waveform. These findings reveal the potential of airside acoustic annealing in refining the structure of two-dimensional colloidal arrays. To elucidate our experimental observations, we delve into the theoretical underpinnings of particle dynamics, driven by classical hydromechanical constraints like surface tension and gravity. Using a qualitative estimate, we shed light on the resonant excitations and their potential role in optimizing the self-assembly process, especially focusing on resonances pertinent for enhancing cluster enlargements. Conclusively, our research, steeped in robust theoretical frameworks and groundbreaking experimental techniques, offers a multifaceted solution for perfecting two-dimensional colloidal arrays. This combined approach not only broadens the scope of acoustically induced crystallization but also charts a path for its adoption across diverse environments, signaling transformative prospects for nanomanufacturing and optical research. [ABSTRACT FROM AUTHOR]

Crystal growth is a complex process with far-reaching implications for high-performance materials across various fields. Recent advancements in structural analysis methods such as polyhedral template matching, which allows semiconductor-specific analysis, coupled with simulation technology, have enabled the comprehensive study of crystallization dynamics in semiconductors. However, the exploration of polycrystalline semiconductors created with minimal external intervention of the crystallization processes is relatively uncharted in comparison with metals. In this study, we employ molecular dynamics to simulate the growth of polycrystalline CdTe/CdS with the assumptions of classical mechanics, a Stillinger–Weber potential, an amorphous substrate, and common vapor growth conditions to allow the polycrystalline structures to evolve naturally. Post-simulation, we identify and analyze impactful structures and events, comparing them to theory and experiment to gain insight into various modes of crystallization dynamics. Two research questions guided the study: (1) How realistic are assumption-less simulated polycrystalline semiconductor structures? (2) To what extent can the approach provide insight into crystallization? The simulations, performed with minimal external control, yield polycrystalline structures mirroring experimental findings. The analysis reveals key crystallization insights, such as the role of amorphous atoms in the transition from nucleation to grain growth and the transformative impact of single events, such as dislocations, on crystallization dynamics. The method paves the way for reproducing and analyzing realistic polycrystalline semiconductor structures with minimal simulation assumptions across various growth modes. [ABSTRACT FROM AUTHOR]

This study is concerned with a theory of two-step nucleation and growth of crystals in a metastable liquid. This mechanism is that crystalline nuclei formation occurs in dense liquid clusters suspended in the solution. These clusters contain higher solution concentration and viscosity, leading to a lower surface free energy barrier and faster phase transition route. The theory is based on growth laws of crystals during the two-step bulk phase transformation. At the initial stage, the crystals evolve in a diffusion-limited environment with almost unchanged supersaturation. At the second stage, they become larger, move beyond these clusters, and evolve in accordance with a hyperbolic tangent law. A generalized particle growth law joining the first and second stages is obtained by stitching the diffusion limited and hyperbolic tangent laws. On this basis, an integrodifferential model of the evolution of a polydisperse ensemble of crystals was formulated and solved. The crystal-size distribution function increases and the solution supersaturation remains practically unchanged until the particle size corresponds to a transition in the particle growth rate from a diffusion-limited branch to a hyperbolic tangent branch. This is followed by an increase in the crystal growth rate, a decrease in the distribution function and solution supersaturation. Then the distribution function increases up to the maximum size of crystals grown in the solution. A sufficiently long time interval of almost constant supersaturation and the N-shaped behavior of the distribution function are the consequences of a two-step nucleation and growth mechanisms. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations are performed to study the crystallization of formamidinium lead iodide. From all-atom simulations of the crystal growth process and the δ-α-phase transitions, we try to reveal the formation of various stack-faulted intermediate defected structures and report various polytypes of formamidinium lead iodide that are observed from simulations. [ABSTRACT FROM AUTHOR]

Optically active spin defects in semiconductors can serve as spin-to-photon interfaces, key components in quantum technologies. Silicon carbide (SiC) is a promising host of spin defects thanks to its wide bandgap and well-established crystal growth and device technologies. In this study, we investigated the oxygen-vacancy complexes as potential spin defects in SiC by means of ab initio calculations. We found that the OCVSi defect has a substantially low formation energy compared with its counterpart, OSiVC, regardless of the Fermi level position. The OCVSi defect is stable in its neutral charge state with a high-spin ground state (S = 1) within a wide energy range near the midgap energy. The zero-phonon line (ZPL) of the OCVSi0 defect lies in the near-infrared regime, 1.11–1.24 eV (1004–1117 nm). The radiative lifetime for the ZPL transition of the defect in kk configuration is fairly short (12.5 ns). Furthermore, the estimated Debye–Waller factor for the optical transition is 13.4%, indicating a large weight of ZPL in the photoluminescence spectrum. All together, we conclude that the OCVSi0 defect possesses desirable spin and optical properties and thus is potentially attractive as a quantum bit. [ABSTRACT FROM AUTHOR]

The precipitation of struvite, a magnesium ammonium phosphate hexahydrate (MgNH4PO4 · 6H2O) mineral, from wastewater is a promising method for recovering phosphorous. While this process is commonly used in engineered environments, our understanding of the underlying mechanisms responsible for the formation of struvite crystals remains limited. Specifically, indirect evidence suggests the involvement of an amorphous precursor and the occurrence of multi-step processes in struvite formation, which would indicate non-classical paths of nucleation and crystallization. In this study, we use synchrotron-based in situ x-ray scattering complemented by cryogenic transmission electron microscopy to obtain new insights from the earliest stages of struvite formation. The holistic scattering data captured the structure of an entire assembly in a time-resolved manner. The structural features comprise the aqueous medium, the growing struvite crystals, and any potential heterogeneities or complex entities. By analysing the scattering data, we found that the onset of crystallization causes a perturbation in the structure of the surrounding aqueous medium. This perturbation is characterized by the occurrence and evolution of Ornstein-Zernike fluctuations on a scale of about 1 nm, suggesting a non-classical nature of the system. We interpret this phenomenon as a liquid-liquid phase separation, which gives rise to the formation of the amorphous precursor phase preceding actual crystal growth of struvite. Our microscopy results confirm that the formation of Mg-struvite includes a short-lived amorphous phase, lasting >10 s. [ABSTRACT FROM AUTHOR]

During devitrification, pre-existing crystallites grow by adding particles to their surface via a process that is either thermally activated (diffusive mode) or happens without kinetic barriers (fast crystal growth mode). It is yet unclear what factors determine the crystal growth mode and how to predict it. With simulations of repulsive hard-sphere-like (Weeks–Chandler–Andersen) glasses, we show for the first time that the same system at the same volume fraction and temperature can devitrify via both modes depending on the preparation protocol of the glass. We prepare two types of glass: conventional glass (CG) via fast quenching and uniform glass (UG) via density homogenization. First, we bring either glass into contact with a crystal (X) and find the inherent structure (CGX/UGX). During energy minimization, the crystal front grows deep into the CG interface, while the growth is minimal for UG. When thermal noise is added, this behavior is reflected in different crystallization dynamics. CGX exhibits a density drop at the crystal growth front, which correlates with enhanced dynamics at the interface and a fast growth mode. This mechanism may explain the faster crystal growth observed below the glass transition experimentally. In contrast, UGX grows via intermittent avalanche-like dynamics localized at the interface, a combination of localized mechanical defects and the exceptional mechanical stability imposed by the UG glass phase. [ABSTRACT FROM AUTHOR]

Experimental and simulation studies were conducted for surface segregation-limited kinetics of nitrogen incorporation into a 4H-SiC crystal during physical vapor transport (PVT) crystal growth. It was revealed that the nitrogen incorporation is kinetically limited by the step-flow velocity on the growing crystal surface of a 4H-SiC crystal; in this study, the surface step-flow velocity at the growth front was deduced from the local inclination angle of the growth front measured from the (000 1 ¯) plane, assuming a uniform growth rate along the c-axis (crystal growth direction) across the growth front, and the nitrogen concentration across the growth front was measured using Raman scattering microscopy. The step-flow velocity dependence of nitrogen incorporation was theoretically analyzed using a two-site-exchange model, and the simulated dependence using the model was in good agreement with the experimental data. On the basis of these experimental and simulation results, kinematical and energetical aspects of nitrogen incorporation at the growth front of a 4H-SiC crystal during PVT growth are discussed. [ABSTRACT FROM AUTHOR]

Salt solubility is generally determined under isotropic stress conditions. Yet, in the context of salt weathering of porous media, mechanical constraints on the in-pore growth of salt crystals are likely to be orientation-dependent, resulting in an anisotropic stress state on the crystal. In this paper, we determine by molecular simulation the solubility of NaCl in water when the crystal is subjected to anisotropic stress. Such anisotropy causes the chemical potential of the crystal to be orientation-dependent, and proper thermodynamic formulation requires describing the chemical potential as a tensor. The solute and crystal chemical potentials are computed from free energy calculations using Hamiltonian thermodynamic integration, and the usual condition of solubility is reformulated to account for the tensorial nature of the crystal chemical potential. We investigate in detail how the uniaxial compression of the crystal affects its solubility. The molecular simulation results led to revisiting the Correns law under anisotropic stress. Regarding the solute, the non-ideal behavior of the liquid phase is captured using Pitzer's ion interaction approach up to high concentrations of interest for in-pore crystallization and beyond the concentrations addressed in the existing literature. Regarding NaCl crystals, the validity of the generalized Gibbs–Duhem equation for a tensorial chemical potential is carefully verified, and it is found that crystallization progresses almost orthogonally to the crystal surface even under high shear stresses. Comparing uniaxial and isotropic compression highlights the major differences in solubility caused by stress anisotropy, and the revisited Correns law offers an appropriate framework to capture this phenomenon. [ABSTRACT FROM AUTHOR]

Metallic glasses have the potential to become transformative materials, but this is hindered by the lack of ability to accurately predict which metallic alloys will form good glasses. Current approaches are limited to empirical rules that often rely on parameters that are unknown until the glasses are made, rendering them not predictive. In this Perspective, properties of metallic liquids at elevated temperatures and how these might lead to better predictions for glass formation are explored. A central topic is liquid fragility, which characterizes the different dynamics of the liquids. What fragility is and how it might be connected to the liquid structure is discussed. Since glass formation is ultimately limited by crystallization during cooling, recent advances in crystal growth and nucleation are also reviewed. Finally, some approaches for improving glass stability and glass rejuvenation for improved plasticity are discussed. Building on a summary of results, some key questions are raised and a prospective for future studies is offered. [ABSTRACT FROM AUTHOR]

The emergence of a crystal nucleus from disordered states is a critical and challenging aspect of the crystallization process, primarily due to the extremely short length and timescales involved. Methods such as liquid-cell or low-dose focal-series transmission electron microscopy (TEM) are often employed to probe these events. In this study, we demonstrate that ion mobility spectrometry-mass spectrometry (IMS-MS) offers a complementary and insightful perspective on the nucleation process by examining the sizes and shapes of small clusters, specifically those ranging from n = 2 to 40. Our findings reveal the significant role of sulfate ions in the growth of adeninediium sulfate clusters, which are the precursors to the formation of single crystals. Specifically, sulfate ions stabilize adenine clusters at the 1:1 ratio. In contrast, guanine sulfate forms smaller clusters with varied ratios, which become stable as they approach the 1:2 ratio. The nucleation size is predicted to be between n = 8 and 14, correlating well with the unit cell dimensions of adenine crystals. This correlation suggests that IMS-MS can identify critical nucleation sizes and provide valuable structural information consistent with established crystallographic data. We also discuss the strengths and limitations of IMS-MS in this context. IMS-MS offers rapid and robust experimental protocols, making it a valuable tool for studying the effects of various additives on the assembly of small molecules. Additionally, it aids in elucidating nucleation processes and the growth of different crystal polymorphs. [ABSTRACT FROM AUTHOR]

• Microscale crystallization phenomena of waste slag is explored visually. • Effect of homogeneous nucleation on thermal treatment of waste slag is substantial. • Crystal growth mode is various as the isothermal temperature increased. • Correlations are obtained to predict the microscale crystallization phenomena. Metal smelting and combustion of solid fuels produce significant quantities of waste slag, leading to issues such as land occupation and environmental pollution. Understanding and controlling the microscale crystallization phenomena of these slags during thermal treatment is crucial for transforming waste slags into materials suitable for carbon capture or glass ceramics. Previous research has primarily focused on macroscopic crystallization behaviors, significantly advancing the utilization of waste slags in cement clinker production. However, macroscopic results are inadequate for precisely controlling the microscale crystallization behaviors of waste slags. Here, we employed the single hot thermocouple technique to visually explore crystal growth modes, shapes, sizes, numbers, and translational rates of the crystal growth front in a representative blast furnace slag under various isothermal temperatures. The results revealed that crystals exhibited five modes as the isothermal temperature gradually increased, including equiaxed, equiaxed & columnar, columnar, columnar & planar, and planar. Moreover, the translational rate of the crystal growth front increased from 0.011 μm·s−1 to 43.7 μm·s−1 with an increase in the isothermal temperature. Simultaneously, the number of crystals decreased from around 104 to 100 μm−2. On this basis, correlations between microscale crystallization behaviors and isothermal temperature were established to fill the current gap. [ABSTRACT FROM AUTHOR]

All-solid-state sodium batteries, renowned for their leak-proof nature and enhanced safety profile, have become a pivotal focus of research. Their viability hinges on the development of robust solid electrolyte materials. Among these, Na 3 Zr 2 Si 2 PO 12 (NZSP) stands out as a particularly promising candidate. However, the practical utility of NZSP has been limited by its relatively modest room temperature conductivity. This paper introduces a novel modification strategy aimed at significantly enhancing room temperature conductivity of NZSP. In the series of experiments, NSZP was synthesized by traditional sintering process with Zn2+ doping and NaF additives. Through the substitution of Zr4+ ions with Zn2+ ions, this innovative approach not only raises the sodium ion concentration but also expands the bottleneck regions within the Na ion transport pathways. This augmentation ultimately translates into heightened grain conductivity. Additionally, the incorporation of NaF during the sintering process induces crystal growth in NZSP, thereby reducing grain boundary concentration and further amplifying grain conductivity's contribution to the overall ionic conductivity. Employing conventional sintering techniques, we successfully synthesized Na 3.3 Zr 1.95 Zn 0.05 Si 2.2 P 0.8 O 12 -0.25NaF (−0.25 NaF indicates that 0.25 mol NaF was added during sintering) electrolyte samples, which demonstrated an impressive high room temperature conductivity of 2.2 × 10−3 S cm−1. This value surpasses the ionic conductivity of undoped NZSP electrolytes by approximately an order of magnitude. Moreover, the Na 3.3 Zr 1.95 Zn 0.05 Si 2.2 P 0.8 O 12 -0.25NaF electrolyte exhibits a remarkable electrochemical window extending up to 4.9 V, accompanied by exceptional cycling stability. These properties render it an ideal candidate for a diverse array of cathode materials. [ABSTRACT FROM AUTHOR]

The zero-dimensional copper halide perovskite Cs 3 Cu 2 I 5 displays extraordinary luminescence and scintillation characteristics, and high-quality crystals are extremely desirable for exploring the commercial applications. Currently, the most critical issue in the solution growth of Cs 3 Cu 2 I 5 crystals is the easy oxidation of halides, which significantly hinders the optimization of crystal qualities. The hypophosphorous acid (H 3 PO 2) has been applied to inhibit the oxidation, nevertheless, the related mechanism is elusive and has been largely ignored. Herein, Cs 3 Cu 2 I 5 crystals have been grown from N, N-Dimethylformamide (DMF) solvent by the antisolvent vapor-assisted crystallization (AVC) method. It is verified that H 3 PO 2 effectively prevents the oxidation of Cs 3 Cu 2 I 5 by rapidly reducing Cu2+ and I 3 −, maintaining the stability of the precursor solution and continuously suppressing oxidation during the whole growth process. Meanwhile, by increasing the acidity of the solution, H 3 PO 2 dissolve precursor colloids and efficiently enhance the solubility of halides. Thus, the addition of H 3 PO 2 favors the rapid growth of centimeter-sized Cs 3 Cu 2 I 5 crystals with well-defined crystallographic planes within several days. As excellent gamma ray scintillator, the crystal exhibits high light yield of 38000 photons/MeV, with energy resolution of 5.6 % under 662 keV radiation from a 137Cs source. This work deeply elucidates new insight into the critical effect of H 3 PO 2 in the DMF based solution crystal growth, facilitating the preparation of large-size and high-performance copper halide perovskite crystals. [ABSTRACT FROM AUTHOR]

The internal modification with rare earth ion doping proved to be a very effective strategy for improving the luminescent properties of NaYF 4 -based upconversion materials. However, greatly enhancing the luminescence efficiency of NaYF 4 :Yb3+/Er3+ remains a major challenge. Herein, the effects of Sn4+ doping on the structure and luminescent performance of such material were explored. The hydrothermal molten-salt method was applied to synthesize the Sn4+-doped NaYF 4 :Yb3+/Er3+ upconversion materials, and their crystal structures, morphologies, surface chemical composition and element states, and luminescence performance were characterized. It was found that Sn4+ doping can significantly enhance the luminescence intensity and tailor the chromaticity of NaYF 4 :Yb3+/Er3+. In particular, the green (G) and red (R) luminescence intensity levels of the 30 mol% Sn4+ doped material were increased by factors of 26.97 and 38.91, respectively. The R/G ratio was incremented from 0.34 for the undoped material to 0.83 for the 40 mol% Sn4+ doped counterpart. The Sn4+ doping led to the change of lattice distortion and crystal growth pattern of NaYF 4 :Yb3+/Er3+. The mechanism for Sn4+ doping to affect the luminescence properties of the prepared upconversion material was also explored. The changes in luminescence intensity levels and R/G ratios could be attributed to the highly asymmetric distorted lattice and crystal field resulting from Sn4+ doping. [ABSTRACT FROM AUTHOR]

In recent years, the shift towards single-crystalline Ni-rich LiNi x Co y Mn 1-x-y O 2 (NCM) cathode materials has intensified the focus on temperature regulation via the solid-state method, aiming to enhance electrochemical capacity and control crystal size. This study investigates how variations in crystal size, indicative of distinct lattice structures, affect lithium ion transport during the electrochemical charging/discharging cycle. Our findings reveal mechanical degradation in NCM samples correlating with increased sintering temperatures of LiOH·H 2 O and NCMOH precursors, as evidenced by nanoindentation tests measuring elastic modulus and hardness. Elevated sintering temperatures were observed to facilitate nucleation and crystal growth, albeit introducing oxygen vacancies potentially detrimental to the initial Coulombic Efficiency within the NCM lattice. This degradation in both mechanical and electrochemical properties underscores the critical impact of sintering temperature on structural integrity. Our systematic analysis provides essential insights into the interplay between structural characteristics and electrochemical performance, offering compelling evidence for the optimization of sintering temperatures in the preparation of NCM cathode materials. [ABSTRACT FROM AUTHOR]

2 μm pulsed lasers not only have critical applications in military, medical, and processing fields but are also an important frontier in laser physics. The development of these pulsed lasers has been hindered by the lack of laser crystals with both high thermal conductivity and broad spectral properties. In this work, Tm, Ho:CaGdAlO4 disordered crystal with ultra-broad emission spectra around 2 μm was achieved successfully by modulating the emission intensities of Tm3+ and Ho3+ ions to the same level. The FWHM of the absorption spectra at 793 nm for the <001> and <100> directions are 18.69 and 19.44 nm, respectively, which is beneficial for commercial laser diode pumping. More importantly, the FWHM of the emission spectrum is 264 nm, which is the widest one reported in the previous literature. The results indicate that the Tm, Ho:CaGdAlO4 crystal with its broader spectra has the potential to generate an ultrashort pulse laser. [ABSTRACT FROM AUTHOR]

High‐quality perovskite (PVK) films is essential for the fabrication of efficient and stable perovskite solar cells (PSCs). However, unstable colloidal particles in PVK suspensions often hinder the formation of crystalline films with low defect densities. Herein, ethylenediaminetetraacetic acid (EDTA) as a colloidal stabilizer into lead iodide (PbI2) is introduced colloidal solutions. EDTA forms chelated complexes with Pb2+, enhancing the electrostatic repulsion and steric hindrance between colloidal particles. This stabilizes the particles and inhibits disordered motion (Brownian motion) and excessive aggregation. As a result, PbI2 films with a uniform hole distribution are formed, providing ample pathways for subsequent PVK film growth and sufficient space. During the film formation process, the replacement of molecules by formamidinium iodide (FAI) and EDTA slows down crystallization, ultimately leading to PVK films with large grain sizes and low defect density. By using this approach, champion power conversion efficiencies (PCEs) of 24.05% for FA0.97Cs0.03PbI3 PSC, 11.08% for CsPbBr3 PSC, and 25.19% for FA0.945MA0.025Cs0.03Pb(I0.975Br0.025)3 PSC are achieved. Moreover, the EDTA‐based FA0.97Cs0.03PbI3 device retains over 90% of its initial PCE after 1000 h at the maximum power point (MPP) under continuous illumination. [ABSTRACT FROM AUTHOR]

Millimetre-scale rhombohedral PCBM crystals were fabricated on multiple substrates, including metalised glass and polymer. The multi-substrate fabrications granted the ability of characterising the crystals composition, magnetically, electrically, and mechanically. Colossal crystals were fabricated with or without P3HT, elucidating novel capabilities of the crystals for flexible and wearable electronics applications. The lone PCBM crystals were characterised for their optical and mechanical properties, whereas the P3HT coated crystals have notable magnetic and conductive performances. The substrate type played a crucial role in property-map of this organic framework, including crystal growth and segregation. The PCBM crystals combined with P3HT hold a promising future for organic photovoltaics and magnetic systems. [ABSTRACT FROM AUTHOR]

Stereoselective inhibition aided by "tailor‐made" polymeric additives is an efficient approach to obtain enantiopure compounds through conglomerate crystallization. The chemical and configurational match between the side groups of polymers and the molecules of undesired enantiomer is considered to be a necessary condition for successful stereoseparation. Whereas in this contribution, we present an effective resolution of chiral pharmaceuticals by using cellulose acetates as the additives, which stereoselectively reside on the specific crystal faces of one enantiomer and inhibit its crystal nucleation and growth through helical pattern and supramolecular interaction complementarity. An investigation of nimodipine serves as a case study to highlight the novelty of this strategy wherein R‐crystals exhibiting an impressive enantiomeric excess value of 97 % can be attained by employing a mere 0.01 wt % cellulose acetate. Guaifenesin and phenyl lactic acid are also well‐resolved by utilizing this methodology. Our work not only brings about a brand‐new design strategy for "tailor‐made" additives, but will also promote the further exploration of the endless potential for utilizing natural biomolecules in chiral recognition and resolution. [ABSTRACT FROM AUTHOR]

This study compares the efficiency of commercially available sorbitol-based clarifying agent (NA) and varying amounts of long chain-branched polypropylene (LCBPP) acting as a specific α-nucleating agent for linear polypropylene (PP). The sorbitol-based clarifying agent, 1,3;2,4-bis(3,4-dimethyl benzylidene)sorbitol (Millad 3988), in concentration 0.2 wt%, and LCBPP in the concentration of 1, 2, 5 and 10 wt% were mixed into PP. The comparison of the effect of NA and long branches under isothermal conditions on the crystallization process, crystallinity and polymorphic composition was realized by differential scanning calorimetry and wide-angle X-ray scattering. The addition of long chain-branched polypropylene, even at the lowest concentration, performs better at higher crystallization temperatures and has a superior effect on the crystallization process, crystallization rate and overall crystallization than the addition of NA. [ABSTRACT FROM AUTHOR]

Bis-[2-(3,4-dihydroxyphenyl)-4,5-diphenyl-1H-imidazol-3-ium] Oxalate ethanol solvate crystal has been isolated from slow solvent evaporation method and the structure was characterized by FT-IR, NMR and Single crystal XRD. The compound crystallizes in the triclinic space group P 1 ¯ with a = 7.7925(16), b = 10.716(3), c = 13.952(3), α = 106.545(5), β = 97.514(5), γ = 110.152(5), V = 1014.0(4) Å3 and Z = 1. The single crystal X-ray data of the compound confirms two proton transfers from an oxalic acid to the pyrimidine-type-nitrogen of two separate imidazole rings. The structure and symmetry of the Imidazolium Oxalate is dictated by N–H⋯O and O–H⋯O hydrogen bonding interactions and are confirmed by hydrogen bonding analysis and hirshfeld surface analysis. The partial double bond character in the imidazolium ring confirms delocalization across the molecular framework. The partial double bond character of the C–O bonds also confirms delocalization in the oxalate anion. The crystal is 3-dimensional structure, with crystal growth in all the crystallographic axis. Computational analysis [DFT, B3LYP/6-311G(d,p)] reveals close correlation of the constrained optimized structure with the experimental data. Imidazolium oxalate crystal form by the protonation of Imidazole compound and complex formation with oxalate ion. [ABSTRACT FROM AUTHOR]

In vitro biomineralization, carried out under laboratory conditions, provides scope for highly controlled crystallization events, at different stages of the formation reaction. This crystallization control is exerted using foreign substances or additives, which are usually organic compounds. Here, we have shown how with the use of homeopathic medicine Symphytum Q, the morphology of calcium carbonate is changed from its rhombohedral, the most stable morphology to spherical morphology, while the phase remains the same. A study has also been done on the formation of gypsum with varying parameters. [ABSTRACT FROM AUTHOR]

Monopotassium orthophosphate (MPOP) crystals in pure form and monopotassium orthophosphate crystals in doped form with non-essential amino acid L-serine (LSMPOP) are obtained by implementing slow evaporation solution growth techniques. The peaks of powder XRD graphical output, while comparing with the powder XRD pattern of pure MPOP, is found that 2θ values shifted slightly for L-serine-doped MPOP and this suggests that the formation of parent material is slightly disturbed by the dopant L-serine. The lattice constant and other crystal characteristics like volume, space group crystal system were analysed in detail by single crystal X-ray diffraction investigations and it is found that it belongs to I-42d space group and tetragonal structure. The infra-red Fourier transforms' spectral studies give information about the functional groups present in the pure and L-serine-doped parent material MPOP. The properties like optical energy gap, lower cut-off wavelength and transmittance were given by ultraviolet visible spectral inspections and the cut-off wavelength is found to be 382 nm for MPOP and 385 nm for LSMPOP, the band gap is found to be 2.85 eV for MPOP and 3.03 eV for LSMPOP. The microhardness of the title materials are calculated by Vickers microhardness studies. The electrical behaviours of MPOP and LSMPOP, such as dielectric constant, ac conductivity, impedance spectroscopy, activation energy are diagnosed and calculated by dielectric analysis. [ABSTRACT FROM AUTHOR]

Political theory has long depended upon a clear boundary between life and non-life. Even work which emphasizes non-human beings (e.g., in animal rights, posthumanism or "new materialism") continues to reinforce the divide between the organic and the inorganic. This article undermines that division, highlighting marginal cases of life. The organicity of certain rocks and biochar, the growth of crystals, the machinic qualities of viruses: all point to an instability in the excluded middle between life and non-life. The article suggests alternative philosophical traditions to which political theory could turn—namely, panpsychism, hylozoism, and traditional animism—as conceptual and theoretical resources to examine these interstices. [ABSTRACT FROM AUTHOR]

Scalable deposition of high-efficiency perovskite solar cells (PSCs) is critical to accelerating their commercial applications. However, a significant number of defects are distributed at the buried interface of perovskite film fabricated by scalable deposition, exhibiting much negative influence on the efficiency and stability of PSCs. Herein, 2-(N-morpholino)ethanesulfonic acid potassium salt (MESK) is incorporated as the bridging layer between the tin oxide (SnO2) electron transport layer (ETL) and the perovskite film deposited via scalable two-step doctor blading. Both experiment and simulation results demonstrate that MESK can passivate the trap states of Sn suspension bonds, thereby enhancing the charge extraction and transport of the SnO2 ETL. Meanwhile, the strong interaction with uncoordinated Pb ions can modulate the crystal growth and crystallographic orientation of perovskite film and passivate buried defects. With employing MESK interface bridging, PSCs fabricated via scalable doctor blading in ambient condition achieve a power conversion efficiency (PCE) of 24.67%, which is one of the highest PCEs for doctor-bladed PSCs, and PSC modules with an active area of 11.35 cm2 achieve a PCE of 19.45%. Furthermore, PSCs exhibit excellent long-term stability, and the unpackaged target device with a storage of 1680 h in ambient condition (25 °C and humidity of 30% relative humidity (RH)) can maintain more than 90% of the initial PCE. The research provides a strategy for constructing a high-performance interface bridge between SnO2 ETL and perovskite film, and achieving efficient and stable large-area PSCs and modules fabricated via scalable doctor-blading process in ambient condition. [ABSTRACT FROM AUTHOR]

The Ni electrodeposition combined with multilayered structure film is a promising strategy in modern optical manufacturing, while less effort has been devoted to comprehending the electrochemical reaction process, which is essential for their practical applications. In view of this, the initial reduction dynamics and nucleation mechanisms of Ni electrodepositions on multilayer W/Si and Cr/C films were analyzed in this work, and the morphological, crystal, and mechanical characteristics of produced Ni electrodeposits were further determined and compared. The results show that the considerably irregular crystals accompanied by high tensile stress of 119.5 MPa were formed for the Ni electrodeposit on W/Si film, which were mainly attributed to the progressive nucleation process with more severe side reaction of hydrogen evolution. By contrast, the instantaneous nucleation mode with lower reduction resistance were revealed for the Ni electrodeposition on Cr/C film, which presented a comparatively fine–grained texture, less roughness, and smaller stress structure. To summarize, the more stable electrochemical reaction process and improved structure uniformity are obtained for the Ni electrodeposition on metal/C–based film, which offers a theoretical guidance for optimized fabrication of multilayer optical devices in extreme ultraviolet, x-ray, and neutron focusing fields. [ABSTRACT FROM AUTHOR]

Aluminum‐doped ZnO (AZO) were successfully prepared on polyimide (PI) film using electrochemical deposition. Field emission scanning electron microscopy (FESEM) analysis revealed that as the aluminum concentration increased, the morphology of AZO nanostructures changed from pellets to nanorods. X‐ray photoelectron spectrometry (XPS) was employed to study the chemical states of undoped and Al‐doped ZnO on a polyimide substrate. The X‐ray diffraction (XRD) patterns of the PI/AZO nanostructures showed a polycrystalline wurtzite structure with a crystallographic orientation along the (002) plane. The XRD analysis also indicated that the average crystallite size decreased from 50.5 nm to 31.0 nm with increasing aluminum concentration (from 0.05 mM to 10 mM). Transmittance analysis revealed that with increasing aluminum concentration, the average optical transmittance in the visible region decreased from 90 % to 75 %. The aluminum concentration has a significant effect on the electrical properties of the samples, as shown by current‐voltage (I–V) and Hall measurements. Among the samples, the AZO/PI film prepared with 5 mM aluminum concentration exhibited the minimum electrical resistivity (4.14×10−2 Ω.cm), the highest carrier density (1.10×1021 cm−3) and the Hall mobility (5.40 cm2 V−1 s−1). We also discuss the possible mechanisms underlying these results compared to undoped ZnO films. This study contributes to the potential applications in flexible electronics and optoelectronics by demonstrating the tunability of AZO nanostructures on a flexible polyimide substrate through controlled aluminum doping. [ABSTRACT FROM AUTHOR]

High-quality inorganic perovskite films are the most vital factor to assemble efficient and stable inorganic perovskite solar cells. Herein, a polyethylene glycol (PEG)-assisted two-step sequential deposition process is proposed to fabricate high-quality CsPbIBr2 perovskite films, wherein PEG is incorporated into a PbBr2 solution to modulate the PbBr2 colloidal properties due to the strong interaction between PEG molecules and PbBr2. The modulation of PbBr2 colloidal properties through adding PEG tunes the crystallization of PbBr2 and leads to the formation of porous PbBr2 films during the first-step deposition process. Such porous PbBr2 films favor CsI penetration during the second-step CsI deposition process and provides sufficient space for perovskite crystal growth and volume enlargement during the subsequent annealing process. As a result, a full-coverage and high-quality CsPbIBr2 perovskite film with reduced defects and enlarged grains is obtained after optimizing the amount of PEG. The assembled carbon-based CsPbIBr2 perovskite solar cell delivers a high power conversion efficiency of 10.26%. Moreover, the unencapsulated CsPbIBr2 cell preserves ∼93% of its initial efficiency after 900 h of storage under ambient conditions. [ABSTRACT FROM AUTHOR]

This article demonstrates the ability of electron diffraction (3D ED, or simply ED) for solving complex structures of active pharmaceutical ingredients (API) and its relevance in the drug development process. The study focuses on febuxostat (FEB), a selective inhibitor used for treating gout. FEB exhibits multiple solid forms, with the crystal structure of the marketed polymorph (form A) being unknown despite its commercial availability. In this work, the crystal structure of form A was successfully determined using both ED and single-crystal X-ray diffraction techniques (SC-XRD). Notably, the crystal growth attempts delivered very small crystals, suitable for ED only, while larger single-crystals for SC-XRD were unintentionally obtained in an experiment aiming for the co-crystallization of FEB with benzoic acid. The results show that ED is a valuable and reliable tool for crystal structure determinations, with comparable accuracy to X-ray crystallography. This study highlights the possibility of incorporating ED in the pharmaceutical research and development process, offering a reliable and efficient approach for crystal structure analysis. It emphasizes the significance of combining crystal structure knowledge with theoretical methods in understanding complex polymorphic systems. Furthermore, it addresses the ED potential in overcoming the challenges in characterizing solid forms across the drug development process. [ABSTRACT FROM AUTHOR]

Organic solvents host the synthesis of high-value crystals used as pharmaceuticals and optical devices, among other applications. A knowledge gap persists on how replacing the hydrogen bonds and polar attraction that dominate aqueous environments with the weaker van der Waals forces affects the growth mechanism, including its defining feature, whether crystals grow classically or nonclassically. Here we demonstrate a rare dual growth mode of etioporphyrin I crystals, enabled by liquid precursors that associate with crystal surfaces to generate stacks of layers, which then grow laterally by incorporating solute molecules. Our findings reveal the precursors as mesoscopic solute-rich clusters, a unique phase favored by weak bonds such as those between organic solutes. The lateral spreading of the precursor-initiated stacks of layers crucially relies on abundant solute supply directly from the solution, bypassing diffusion along the crystal surface; the direct incorporation pathway may, again, be unique to organic solvents. Clusters that evolve to amorphous particles do not seamlessly integrate into crystal lattices. Crystals growing fast and mostly nonclassically at high supersaturations are not excessively strained. Our findings demonstrate that the weak interactions typical of organic systems promote nonclassical growth modes by supporting liquid precursors and enabling the spreading of multilayer stacks. Organic solvents are used to produce high-value crystals such as pharmaceuticals, organic semiconductors, and optical devices, but our understanding of the fundamental processes of crystal growth from organic solutions is limited. Here, the authors use time-resolved in situ atomic force microscopy to show a nonclassical, dual growth mode of etioporphyrin I crystals from mesoscopic solute-rich clusters. [ABSTRACT FROM AUTHOR]

The morphology of the photoactive layer plays an important role in both the photoelectric effect and device performance of solution‐processed organic solar cells (OSCs). Optimizing the morphology requires precise control over the complex film formation kinetics, which are influenced by a range of factors from the solution state to the solid‐film state. This review delves into the in situ characterization technologies employed to understand the active layer formation process and explores strategies for controlling film formation during key stages, including solution aggregation, nucleation, crystal growth, and phase separation. Special attention is given to the mechanism by which these strategies enable real‐time morphology control during the printing process and their potential to facilitate direct printing of active layers with optimized morphology. The goal is to offer valuable insights and guidance for managing film formation kinetics in solution‐processed OSCs, ultimately addressing the challenges of real‐time morphology control in scale‐up printing and paving the way for high‐throughput production of post‐processing‐free devices. [ABSTRACT FROM AUTHOR]

Passivation of perovskite crystals is a crucial strategy to improve the efficiency and stability of perovskite solar cells (PSCs). Zwitterions, which contain both positive and negative charges in the molecule, can be used to passivate perovskite crystals. However, these materials strongly interact with each other, resulting in extremely low solubility in common organic solvents. The low solubility of zwitterions hinders the formation of uniform films, which negatively affects perovskite crystal growth. In this study, a liquid‐type zwitterion (LTZ) is synthesized by modulating intermolecular interactions of the zwitterion (3‐(1‐Pyridinio)‐1‐propanesulfonate). By suppressing intermolecular interactions, the solubility and processibility of the zwitterion in common organic solvents are successfully improved. The well‐distributed LTZ‐treated films are obtained, resulting in better electrical properties for the PSCs compared to solid‐type zwitterion‐based devices. With these characteristics, the resulting device achieves a power conversion efficiency of 24.9% with excellent thermal stability (under 60 °C and N2 atmosphere), maintaining over 80% of its initial efficiency for 1968 h. In addition, the PSC module (active area of 32.7 cm2) achieves an improved efficiency of 19.86% with high open‐circuit voltage and fill factor. The results suggest that interface engineering with an LTZ has the potential to fabricate efficient and stable PSCs. [ABSTRACT FROM AUTHOR]

InGaN, a group‐III nitride semiconductor, is expected to be widely used in the field of optoelectronics, owing to its excellent physical properties. However, InGaN has various limitations. This study reports face‐to‐face annealing (FFA) using vapor‐phase and in‐plane mass transport to improve the surface flatness of an InGaN template. InGaN layers are grown on a GaN template that is grown on a c‐plane sapphire substrate using metal–organic vapor‐phase epitaxy. NH3‐assisted FFA is performed at 1050 °C for 20 min, causing V‐pits to vanish from the InGaN template despite their initial density of 3.3 × 108 cm−2. The surface condition of the lower InGaN layer is worse than that of the upper InGaN layer due to the FFA‐induced upward mass transport from the lower layer, thereby eliminating the V‐pits. Compositional analysis of the upper layer through Auger electron spectroscopy and energy‐dispersive X‐ray spectroscopy reveals In peaks despite high‐temperature annealing, thus confirming the presence of InGaN. The results of this study offer possibilities for future InGaN crystal growth and InGaN‐based device fabrication. [ABSTRACT FROM AUTHOR]

Crystal polymorphism, characterized by different packing arrangements of the same compound, strongly ties to the physical properties of a molecule. Determining the polymorphic landscape is complex and time‐consuming, with the number of experimentally observed polymorphs varying widely from molecule to molecule. Furthermore, disappearing polymorphs, the phenomenon whereby experimentally observed forms cannot be reproduced, pose a significant challenge for the pharmaceutical industry. Herein, we focused on oxindole (OX), a small rigid molecule with four known polymorphs, including a reported disappearing form. Using crystal structure prediction (CSP), we assessed OX solid‐state landscape and thermodynamic stability by comparing predicted structures with experimentally known forms. We then performed melt and solution crystallization in bulk and nanoconfinement to validate our predictions. These experiments successfully reproduced the known forms and led to the discovery of four novel polymorphs. Our approach provided insights into reconstructing disappearing polymorphs and building more comprehensive polymorph landscapes. These results also establish a new record of packing polymorphism for rigid molecules. [ABSTRACT FROM AUTHOR]

Microscopic evaluation is one of the most effective methods in materials research. High-quality images are essential to analyze microscopic images using artificial intelligence. To overcome this challenge, we propose the machine learning of "fake micrographs" in this study. To verify the effectiveness of this method, we chose to analyze the optical microscopic images of the crystal growth process of a Ge thin film, which is a material in which it is difficult to obtain a contrast between the crystal and amorphous states. By learning the automatically generated fake micrographs that mimic the crystal growth process, the machine learning model can now identify the low-resolution real micrographs as crystalline or amorphous. Comparing the three types of machine learning models, it was found that ResUNet ++ exhibited high accuracy, exceeding 90%. The technology developed in this study for the automatic and rapid analysis of low-resolution images is widely helpful in material research. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal CrystEngComm, which focuses on the design and understanding of solid-state and crystalline materials. It includes a list of papers featured in the issue, covering topics such as the photothermal weak absorption of a crystal, halogen bonding proclivity in cocrystals, and the structure and electrical properties of doped single crystals. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document also mentions approved training courses offered by the society. [Extracted from the article]

K0.5Na0.5NbO3 (KNN) crystals have great application prospects due to their excellent piezoelectric properties, high Curie temperature, and environmental friendliness. Currently, KNN crystals grown by the seed-free solid-state crystal growth (SFSSCG) method exhibit relatively high dielectric loss. In order to reduce their dielectric loss, Cu, Bi and Mn co-doped KNN lead-free piezoelectric single crystals were prepared by the SFSSCG method. The effects of the CuO doping content on the structure and electrical properties of (1 − x)(0.996KNN–0.004BiMnO3)–xCuO crystals were systematically studied. The results show that an appropriate doping amount of CuO is beneficial for the growth of the crystals and the improvement of electrical properties. When the diameter of the billets is 40 mm, the maximum crystal size of 25 × 21 × 2 mm3 is obtained. All crystals have a typical perovskite structure almost with a single orthorhombic phase and are very compact almost without holes. The minimum average domain width of 276 nm is obtained for the crystal at x = 0.005. The KNN crystals exhibit normal ferroelectric characteristics and a space-charge-limited-conduction (SCLC) mechanism. The introduction of Cu2+ ions reduces the dielectric loss of the crystal and increases its piezoelectric and dielectric properties. The Cu, Bi and Mn co-doped KNN crystals achieve excellent comprehensive properties: d33 = 314 pC N−1, Pr = 29.9 μC cm−2, Ec = 10.1 kV cm−1, = 869 pm V−1, Qm = 56.8, Kt = 0.38, tan δ = 0.013 and TC = 409 °C. This provides a route to improve the electrical properties of KNN-based crystals. [ABSTRACT FROM AUTHOR]

In optical materials, the development of absorbers for a wide spectrum is a focal point of research. A pivotal challenge lies in ensuring the stability and durability of optical absorbers, particularly at elevated temperatures. This study introduces a novel approach to creating absorbers with diverse colors, focusing on the synthesis and properties of black crystal wires. In contrast to black gold nanoparticle (Au NP) precipitates, which change color within hours under similar conditions, the method involves strategically trapping Au NPs within defects during the growth of single crystals. This results in black crystal wires that not only exhibit broadband absorption but also maintain exceptional stability even under prolonged exposure to high temperatures. The method also involves the controlled synthesis of colorless and red crystal wires. As a proof of concept, these stable black Au crystal wires demonstrate superior performance in photothermal conversion applications. The methodology, derived from the crystal growth process, presents a defect template that offers a novel approach to material design. Furthermore, these unique crystals, available in various colors, hold significant promise for a range of unexplored applications. [ABSTRACT FROM AUTHOR]

Recent studies have revealed that stony corals create their extracellular skeletons via biologically controlled calcification, in which amorphous calcium carbonate (ACC), regarded as precursors of aragonite crystals, have been observed at nanoscale using electron microscopy. However, the exact mechanism by which ACC is generated, and how it contributes to skeletal growth in coral calcifying tissue, remains enigmatic. The septal skeleton of an individual polyp is composed of radially aligned plates extending upward from the aboral calcifying tissue. This structure includes microstructure known as the centers of calcification (CoC). However, despite its importance, direct in vivo observation of septal growth has not been reported. Observations under transmitted illumination using polarized light microscopy on calcifying tissue of young Acropora digitifera revealed small crystals, a few micrometers in size, that accompany subtle movements and that emerge exclusively on the inner wall of the pocket in extracellular calcifying fluid (ECF). Crystal growth initiated from small, scattered crystals on a glass plate resembles this phenomenon observed in coral skeletons. Time-lapse photographs of 12 individuals in early primary polyp settlement revealed this process in three individuals, documenting 13 of these crystal events. This phenomenon occurred solely at the bases of subsequently formed septa. These crystals differ notably from fusiform crystals and from dumbbell-like or rod-like crystals growing individually. Upright two-photon microscopy captured movement of sub-micron-sized fluorescent calcein-accumulating particles, emphasizing their presence on the surface of the growing fronts of septa. Methodological advances that facilitate comprehensive in vivo observation of sub-micron-sized structures, calcein-accumulating particles to the skeleton, are needed to develop a more detailed understanding of coral skeletal growth. [ABSTRACT FROM AUTHOR]

Borosilicate glasses are the primary waste forms for the industrial immobilization of high‐level liquid waste. Yet, the compositional variation of waste glasses can form the diopside phase, which can be detrimental to the melting process and the properties of the final glass products. This study prepared simulated waste glasses with variable contents of alkaline earth metals, boron, transition metals, and rare earth metal oxide and subjected them to heat treatments. The effect of the compositional variation on the diopside crystallization behavior was explored using differential scanning calorimetry, X‐ray diffraction, optical microscopy, and scanning electron microscopy‐energy dispersive spectroscopy. The results revealed that the average size of diopside crystals was proportional to the square root of the heat treatment durations. Increased contents of alkaline earth and transition metal oxides could contribute to the growth of diopside crystals, while boron oxide tended to inhibit it. Finally, a prediction model correlating the average crystal size, compositional variation, and heat treatment durations was discussed. [ABSTRACT FROM AUTHOR]

Based on the Matusita–Sakka equation and the exothermic peaks in the differential thermal analysis (DTA) curves, in silicate glasses with complex crystallization processes containing the precipitation of two or more crystal phases, the effects of particle sizes on the calculations of crystal growth dimensionality and activation energy of crystal growth have been studied in depth. In crystallization processes with two or more crystal phases but one exothermic peak, 0.3 mm is considered as the boundary between the fine and the coarse particles in this type of glass. For glass samples with a particle size less than 0.3 mm, the crystal growth dimensionality is a three‐dimensional mechanism, and EG increases slightly with decreasing particle size. For glass samples with a particle size greater than 0.3 mm, the crystal growth dimensionality is a two‐dimensional mechanism, and EG increases with decreasing particle size. The EG for the fine‐particle starting material is much lower than that of the coarse‐particle starting material. In crystallization processes with two or more crystal phases and two exothermic peaks, 0.104 mm is considered as the boundary between the fine and the coarse particles in this type of glass raw material. For the first peak, in glass samples with a particle size less than 0.104 mm, the crystal growth mechanism is mainly one‐dimensional growth, and EG increases slightly with decreasing particle size. And for glass samples with particle size greater than 0.104 mm, the crystal growth mechanism is mainly two‐dimensional growth, and EG decreases with decreasing particle size. For the second peak, the crystal growth mechanism is mainly a three‐dimensional growth, and EG increases with decreasing particle size. [ABSTRACT FROM AUTHOR]

High carrier recombination causes a huge waste of photogenic charge, which severely restrains the photocatalytic efficiency. Creating polarization electric field by polar photocatalytic materials proves effective to promote charge separation, while developing efficient polarization strategy is challenging and the related micromechanism remains obscure. Here, overall polarization is achieved in Bi2MoO6 single crystal photocatalyst by lateral growth of the nanoplate along {010} facets. Gradual elongation of equatorial Mo─O bonds along the MoO6 octahedral layer occurs, while the length of apical Mo─O bonds basically remains unchanged, thus allowing the large asymmetric distortion of MoO6 octahedron for producing the microscopic polarization. Meanwhile, the lateral growth of Bi2MoO6 nanoplates enables the accumulation of distorted polar units, further increasing the polarization intensities. The inside‐out crystal polarization significantly promotes the separation and migration of photogenerated charge carriers. The finely polarized Bi2MoO6 nanoplates exhibit an exceptional photocatalytic selective oxidation rate of benzyl alcohol (BA) to benzaldehyde (BAD) under visible light irradiation (Conversion (Con.) ≈100% within 30 min, Selectivity (Sel.) ≥95%), over 70.7 times that of original Bi2MoO6 nanosheets, on the condition of comparable O2 adsorption capability. This study advances atomic‐level mechanistic insight into polarized materials toward precise design of high‐performance photocatalysts. [ABSTRACT FROM AUTHOR]

Calcium oxalate (CaOx) crystallization is a common phenomenon that contributes to various kidney disorders and stone formation, as well as the formation of scale in industrial processes. The inhibition of CaOx is an area of intense scientific interest in the field of materials science due to its relevance to biomineralization. The present study investigated the effects of pectin (PE) and sodium alginate (SA), two natural polymers, on the growth of CaOx crystals using a batch crystallization method in aqueous solutions at 37 °C with different concentrations (0.5, 1, 5, and 10 ppm). The results of the study showed that both PE and SA were effective inhibitors of CaOx crystal growth, with the highest inhibition observed at a concentration of 10 ppm, reaching 80 %. PE did not significantly affect the size of the crystals, while SA reduced their size as the concentration increased. These findings contribute to our understanding of the potential of natural polymers as non‐toxic inhibitors of CaOx crystal growth. [ABSTRACT FROM AUTHOR]

Bone grafting is crucial for bone regeneration. Recent studies have proposed the use of calcium citrate (CC) as a potential graft material. Notably, citrate does not inhibit hydroxyapatite (HAp) formation at specific calcium-to-citrate molar ratios. Octacalcium phosphate (OCP)/gelatine (Gel) composites, which are commonly produced from porcine Gel, are valued for their biodegradability and bone replacement capability. This study introduces fish Gel as an alternative to porcine Gel because of its wide acceptance and eco-friendliness. This is the first study to examine the interaction effects between two osteogenic materials, OCP/CC, and the influence of different gelatine matrix components on HAp formation in an SBF. Samples with varying CC contents were immersed in an SBF for 7 d and analysed using various techniques, confirming that high CC doses prevent HAp formation, whereas lower doses facilitate it. Notably, small-sized OCP/CC/porcine Gel composites exhibit a high HAp generation rate. Porcine Gel composites form denser HAp clusters, whereas fish Gel composites form larger spherical HAps. This suggests that lower CC doses not only avoid inhibiting HAp formation but also enhance it with the OCP/Gel composite. Compared with porcine Gel, fish Gel composites show less nucleation but an increased crystal growth for HAp. [ABSTRACT FROM AUTHOR]