Journal of Crystal Growth最新文献

{"title":"Modeling solution concentration in cooling crystallization using an ultrasonic probe and image monitoring","authors":"Junjie Li ,&nbsp;Yiting Xiao ,&nbsp;Bo Kong","doi":"10.1016/j.jcrysgro.2025.128178","DOIUrl":"10.1016/j.jcrysgro.2025.128178","url":null,"abstract":"<div><div>Supersaturation during the crystallization process has been a primary focus of research for many years. The ability to measure solution concentration in situ is essential for improving our understanding and control of crystallization. In this paper, we present a solution concentration model for dynamic cooling crystallization based on ultrasonic speed, using L-glutamic acid (LGA) as the case study. The speed of sound and temperature changes of the solution were recorded during the cooling crystallization process. The collected data was categorized into the undersaturated zone (USZ) and the metastable zone (MSZ) for model development. To accurately distinguish between these intervals, a noninvasive imaging device was employed to capture the exact moment of crystal formation. Our results demonstrate the feasibility of using an ultrasonic probe for in situ monitoring of concentration changes during cooling crystallization. Furthermore, an experiment involving LGA cooling crystallization was carried out to validate the model’s sensitivity in detecting the crystallization process.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"662 ","pages":"Article 128178"},"PeriodicalIF":1.7,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cost-effective, hydride-free aqueous synthesis of CdTe quantum dots enabled by using ammonia as the reducing agent","authors":"Van-Thao Ta ,&nbsp;Duy-Khanh Nguyen ,&nbsp;Xuan-Bach Nguyen ,&nbsp;Phuong-Nam Nguyen ,&nbsp;Sinh-Hung Nguyen ,&nbsp;Xuan-Dung Mai","doi":"10.1016/j.jcrysgro.2025.128182","DOIUrl":"10.1016/j.jcrysgro.2025.128182","url":null,"abstract":"<div><div>The development of a simple, cost-effective, and green method to synthesize CdTe quantum dots (QDs), which are a key nanomaterial in sensing, bioimaging, and immunofluorescence analysis is highly desirable. In this study, we used ammonia in lieu of common hydride reductant to synthesize CdTe QDs by simple refluxing aqueous solutions of cadmium salt, sodium tellurite, and 3-mercaptopropionic acid (MPA). The obtained CdTe QDs were characterized by absorption and photoluminescent spectroscopies, X-ray diffraction (XRD), and transmission electron microscope (TEM). The absorption window and the emission color of QDs were facile controlled over the green–red range by varying the refluxing time. As the QD size increased the crystal structure transformed from CdTe to a CdTeS alloyed form. The results demonstrated herein suggest a cost-effective method for production of CdTe QDs.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"661 ","pages":"Article 128182"},"PeriodicalIF":1.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Low and high temperature magnetic properties of MgFe2O4 nanoparticles synthesized by a simple egg white albumin route","authors":"Annrose Sunny ,&nbsp;Kasarapu Venkataramana ,&nbsp;Y. Ranjith Kumar ,&nbsp;M. Vasundhara","doi":"10.1016/j.jcrysgro.2025.128174","DOIUrl":"10.1016/j.jcrysgro.2025.128174","url":null,"abstract":"<div><div>Ferrite type magnetic nanoparticles composed of iron oxide and a metallic element have been attracting considerable interest in manifold applications due to their valuable physical, mechanical, optical, catalytic, and magnetic properties. However, the magnetic properties of ferrite nanoparticles produced via various conventional methods often fall short of the desired specifications for many applications. It is essential to develop an easy, cost-effective, and non-toxic method of preparation. A relatively facile, cost-effective and environment friendly method has been a key focus of research. This study aims to synthesize the MgFe₂O₄ (MFO) spinel ferrite using eco-friendly freshly extracted egg-white albumin method and study the detailed structural as well as the high temperature magnetic characteristics over a wide range of temperature from 2 K to 900 K. The phase purity, particle size, morphology, surface features, elemental confirmation, optical properties, elemental states as well as the magnetic characteristics of the prepared MFO nanoparticles were discussed. The prepared MFO nanoparticles were exhibited a cubic crystal structure in confirmation to a space group of Fd-3 m with an average particle size of 20 nm. UV–Visible absorption analysis of MFO nanoparticles showed an optical band gap of 3.32 eV. Mixed spinel type of MFO is confirmed from XPS spectra. The temperature variation of hysteresis loop suggested a super paramagnetic like behavior, however, a finite coercivity (H_c) was observed. The H_c, M_r, and M_s of the MFO nanoparticles were observed to be 50Oe, 2 emu/g and 26 emu/g, respectively. It was observed from the e M_r/M_s ratio of MFO nanoparticles that the particles are transforming into multi domain in nature above 100 K. The temperature variation of magnetization studies revealed a transition temperature is at around 588 K. Detailed magnetic behavior is investigated and explained by the models supported by theoretical studies.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"662 ","pages":"Article 128174"},"PeriodicalIF":1.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Growth of hexagonal BN crystals by traveling-solvent floating zone","authors":"Eli Zoghlin ,&nbsp;Juliette Plo ,&nbsp;Gaihua Ye ,&nbsp;Cynthia Nnokwe ,&nbsp;Reina Gomez ,&nbsp;Austin Ferrenti ,&nbsp;Satya Kushwaha ,&nbsp;Rui He ,&nbsp;Stephen D. Wilson ,&nbsp;Pierre Valvin ,&nbsp;Bernard Gil ,&nbsp;Guillaume Cassabois ,&nbsp;James H. Edgar ,&nbsp;Tyrel M. McQueen","doi":"10.1016/j.jcrysgro.2025.128164","DOIUrl":"10.1016/j.jcrysgro.2025.128164","url":null,"abstract":"<div><div>Large, high-purity single-crystals of hexagonal BN (h-BN) are essential for exploiting its many desirable and interesting properties. Here, we demonstrate via X-ray tomography, X-ray diffraction and scanning electron microscopy that h-BN crystals can be grown by traveling-solvent floating-zone (TSFZ). The diameters of grown boules range from 3 – 5 mm with lengths from 2 – 10 mm. Tomography indicates variable grain sizes within the boules, with the largest having areas of <span><math><mo>≈</mo></math></span> 1 mm <span><math><mo>×</mo></math></span> 2 mm and thickness <span><math><mo>≈</mo></math></span> 0.5 mm. Although the boules contain macroscale flux inclusions, the h-BN lattice itself is of high quality for samples grown under optimized conditions. The currently optimized growth procedure employs an Fe flux, moderate N<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> pressure (<span><math><mrow><msub><mrow><mi>P</mi></mrow><mrow><mi>N</mi><mn>2</mn></mrow></msub><mo>≈</mo></mrow></math></span> 6 bar), and a growth rate of 0.1 mm/h. Raman spectroscopy for an optimized sample gives an average linewidth of 7.7(2) cm⁻¹ for the E<span><math><msub><mrow></mrow><mrow><mi>2g</mi></mrow></msub></math></span> intralayer mode at 1365.46(4) cm⁻¹ and 1.0(1) cm⁻¹ for the E<span><math><msub><mrow></mrow><mrow><mi>2g</mi></mrow></msub></math></span> interlayer shear mode at 51.78(9) cm⁻¹. The corresponding photoluminescence spectrum shows sharp phonon-assisted free exciton peaks and minimal signal in the energy range corresponding to carbon-related defects (<span><math><mi>E</mi></math></span> = 3.9 – 4.1 eV). Our work demonstrates the viability of growing h-BN by the TSFZ technique, thereby opening a new route towards larger, high-quality crystals and advancing the state of h-BN related research.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"661 ","pages":"Article 128164"},"PeriodicalIF":1.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of the crystal size and chemical composition on the optical properties of diamond films grown by hot filament chemical vapor deposition","authors":"Jorge Montes ,&nbsp;Jorge Vazquez ,&nbsp;Jorge Jurado ,&nbsp;Ángela Marín ,&nbsp;Jesús Alcántar ,&nbsp;Hugo Tiznado ,&nbsp;Frank Romo ,&nbsp;Orlando Auciello ,&nbsp;Oscar Contreras ,&nbsp;Rafael García-Gutiérrez","doi":"10.1016/j.jcrysgro.2025.128166","DOIUrl":"10.1016/j.jcrysgro.2025.128166","url":null,"abstract":"<div><div>This article is focused on describing the optical properties of different polycrystalline diamond thin films grown by hot filament chemical vapor deposition (HFCVD). The study correlates the influence of the crystal size and the composition to the optical properties of the diamond thin films. It was found that the diamond films grain sizes are depending on the precursor gases flow rates during film growth. All diamond films grown in this work exhibit the Raman peak corresponding to the G-band signal at 1560 cm⁻¹ associated to C–C sp² chemical bonds of C atoms in gran boundaries. Ellipsometry was used to determine the optical constants and refractive index of these polycrystalline diamond films using light beam 633 nm wavelength. The refractive index for micro-crystalline diamond (MCD) and nano-crystalline diamond (NCD) films was 2.33 and the ultra-nanocrystalline (UNCD) films presented a refractive index of 2.62. This research is an attempt to provide valuable information on the relation between the films structure, surface topography, chemical composition, and optical properties for a series of polycrystalline diamond films grown by HFCVD. The polycrystalline diamond films synthetized in this work should find applications in the fabrication of sensors, planar waveguide and in the development of opto-electronic devices.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"662 ","pages":"Article 128166"},"PeriodicalIF":1.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Alloyed CeCaxFe1-xO3-δ: A calcium doped cerium iron oxide nanomaterial for photo-fenton degradation","authors":"A. Ashwini ,&nbsp;G. Kaladevi ,&nbsp;Mary George ,&nbsp;Subash C.B. Gopinath","doi":"10.1016/j.jcrysgro.2025.128177","DOIUrl":"10.1016/j.jcrysgro.2025.128177","url":null,"abstract":"<div><div>The widespread application of mixed metal iron oxide materials in diverse environmental contexts makes them highly significant in heterogeneous catalysis. This study focuses on the synthesis of CeCa_xFe_1-xO_3-δ (x = 0, 0.2, 0.5, 0.8, and 1) nanomaterials using the sol–gel method and explores their structural, electrical, magnetic, optical, and photocatalytic properties. Comprehensive characterization was performed using Powder X-ray Diffraction (PXRD), Fourier Transform Infrared Spectroscopy (FTIR), High-Resolution Transmission Electron Microscopy (HRTEM), Brunauer–Emmett–Teller (BET) surface area analysis, Vibrating Sample Magnetometry (VSM), and UV–Visible Diffuse Reflectance Spectroscopy (UV-DRS). The diffraction peaks confirmed the formation of CeFeO₃-based structures. The magnetic behavior of the materials was analyzed through saturation magnetization, remanent magnetization, and coercivity. The optical properties, particularly in the visible region, motivated further exploration of the photo-Fenton activity of these nanomaterials, highlighting their potential in environmental remediation applications.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"662 ","pages":"Article 128177"},"PeriodicalIF":1.7,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143815281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optical and photocatalytic properties of nickel oxide nanoparticles","authors":"Misganu Chewaka Fite,&nbsp;Soressa Desta Karse,&nbsp;Lense Megersa Gode","doi":"10.1016/j.jcrysgro.2025.128163","DOIUrl":"10.1016/j.jcrysgro.2025.128163","url":null,"abstract":"<div><div>This study investigates the optical and photocatalytic properties of Nickel Oxide (NiO) nanoparticles synthesized via co-precipitation at 400 °C for 6 h using nickel nitrate hexahydrate and sodium hydroxide. Characterization techniques, including X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), energy dispersive X-ray analysis (EDX), and UV–vis spectroscopy, were employed. XRD confirmed the NiO product with a face-centered cubic structure and a crystallite size of 11.32 nm. FTIR analysis identified functional groups associated with NiO formation. SEM revealed agglomerated nanoparticles of approximately 22.34 nm in size with a spherical shape. The synthesized NiO exhibited a strong UV absorption peak and an optical band gap of 4.39 eV. The synthesized NiO nanoparticles effectively degraded methylene blue under sunlight. The photocatalytic activity was optimized with catalyst dosages of 2 mg, 5 mg, and 10 mg. The 10 mg dose achieved the highest degradation efficiency of 92.32 % in 40 min, while 2 mg and 5 mg also exhibited substantial degradation, achieving rates of 87.08 % and 87.48 %, respectively. A reusability study indicated excellent stability and photocatalytic activity. These findings suggest NiO nanoparticles’ potential for wastewater treatment applications.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"660 ","pages":"Article 128163"},"PeriodicalIF":1.7,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal stress analysis and growth of high quality La3Ga5SiO14 crystals","authors":"Xianyang Wang ,&nbsp;Yutong Fan ,&nbsp;Peng Dai ,&nbsp;Cheng Ji ,&nbsp;Jian Wu ,&nbsp;Liming Shen ,&nbsp;Shuai Wang ,&nbsp;Ningzhong Bao","doi":"10.1016/j.jcrysgro.2025.128167","DOIUrl":"10.1016/j.jcrysgro.2025.128167","url":null,"abstract":"<div><div>Langasite (La₃Ga₅SiO₁₄, LGS) crystals have garnered significant attention due to their excellent piezoelectric and photoelectric properties. However, the issue of cracking during the crystal growth process has long remained a persistent challenge in this field. This work numerically simulates the stress distribution of crystals prone to cracking during the Czochralski growth process. The results demonstrate that the thermal stress at the shoulder of the crystal is relatively high, often resulting in surface cracking in this region. By optimizing the temperature field structure, 2-inch crack-free LGS crystals with high macroscopic quality were grown in air. The crystal shows high crystallographic uniformity, with an average rocking curve full width at half maximum (FWHM) of approximately 32.02″ for a 2-inch wafer. The crystal demonstrates excellent optical transmittance (∼80%) and stability after annealed at high-temperature in various atmospheres. These findings provide valuable guidance for achieving large-sized, high-quality LGS crystals.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"661 ","pages":"Article 128167"},"PeriodicalIF":1.7,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of a numerical model for Czochralski growth of cesium iodide and calcium fluoride","authors":"Arved Wintzer,&nbsp;Iason Tsiapkinis,&nbsp;Stefan Püschel,&nbsp;Christo Guguschev,&nbsp;Kaspars Dadzis","doi":"10.1016/j.jcrysgro.2025.128155","DOIUrl":"10.1016/j.jcrysgro.2025.128155","url":null,"abstract":"<div><div>Numerical modeling of the Czochralski (CZ) growth process, which includes the multiphysical interactions of electromagnetism, heat transfer, phase change, and melt flow, is an essential tool for process development and optimization. However, validation of such models is mostly insufficient due to the lack of in-situ measurement data, and open-source models are hardly available. To address these issues, a new 2D and 3D CZ growth model has been developed using the open-source tools Elmer for global time-harmonic electromagnetism, steady-state heat transfer and phase change modeling, coupled with OpenFOAM for transient or steady-state melt flow modeling. The model is published under an open-source license. The model is validated with a focus on electromagnetism and heat transfer using a model experiment with cesium iodide (CsI, melting point: 627<!--> <!-->°C), targeting oxide/fluoride materials. For the 2D model, a satisfying agreement between model experiment and simulation regarding crucible and crystal temperature is achieved in regions with constant crystal diameter. With the 3D model, 3D flow patterns caused by an asymmetric crucible temperature distribution due to an asymmetric magnetic field of the induction heater are observed and in reasonable agreement with the experiment. However, both models yield heater currents up to 38<!--> <!-->% higher than those observed in the experiment. The transferability of the validation results to calcium fluoride (CaF₂) growth for laser cooling application is discussed. The CaF₂ growth process is modeled in 3D to investigate the cause of a rough crystal surface observed in the experiment. It might be caused by a rotating 3D flow structure, while the observation window in the insulation and after-heater is of low influence on the temperature distribution and, thus, the crystal surface structure.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"661 ","pages":"Article 128155"},"PeriodicalIF":1.7,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crystallization agents modifying conversion of phosphogypsum to α-hemihydrate gypsum: Effects of the charge and molecular polarity of carbon-based oxygen atoms","authors":"Qiangwei Hu ,&nbsp;Haixiang Xu","doi":"10.1016/j.jcrysgro.2025.128161","DOIUrl":"10.1016/j.jcrysgro.2025.128161","url":null,"abstract":"<div><div>To promote the resource utilization of phosphogypsum (PG) and reduce environmental pollution, this study utilizes the autoclave method with various organic acids and their sodium salts as crystallization agents to convert PG into α-hemihydrate gypsum (α-HH). The study investigates the effects and mechanisms of these crystallization agents on the crystal morphology and strength of α-HH using X-ray diffraction, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), zeta potential measurements, and molecular dynamics simulations. The results indicate that adding various organic acids and their sodium salts as crystallization agents can effectively regulate the strength and crystal morphology of the α-HH obtained from PG to reduce the aspect ratio of the α-HH crystals. Sodium citrate demonstrated the optimal efficacy as a crystallization agent in controlling the crystal morphology of α-HH. Reducing the aspect ratio to 1.25:1. The absolute dry compressive strength increased to 40.3 MPa when sodium citrate was used, meeting the requirements for high-strength gypsum, specifically α40. Sodium salts of various organic acids demonstrate greater ability than their corresponding organic acids in regulating the crystal morphology of α-HH. This is mainly attributed to the fact that compared to organic acids, the carbon-based oxygen atoms in sodium salts have stronger electron-donating capacity and higher molecular polarity. These characteristics facilitate the formation of cyclic chelates with Ca²⁺ ions within α-HH crystals, thereby enhancing crystal morphology control and increasing α-HH strength.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"660 ","pages":"Article 128161"},"PeriodicalIF":1.7,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}