Crystal Research and Technology最新文献_第8页

Finite Element Simulation of Temperature Distribution in Growth Chamber for Verneuil‐Grown SrTiO3 Crystal Verneuil生长SrTiO3晶体生长室温度分布的有限元模拟

IF 1.5 4区材料科学

Crystal Research and Technology Pub Date : 2021-03-22 DOI: 10.1002/crat.202000185

Xudong Liu, Lei Wang, Huiyun Yan, X. Bi, Xudong Sun

引用次数: 0

Influence of Annealing Temperature Modulation on the Structural and Optical Properties of ZnSe Thin Films 退火温度调制对ZnSe薄膜结构和光学性能的影响

IF 1.5 4区材料科学

Crystal Research and Technology Pub Date : 2021-03-22 DOI: 10.1002/crat.202000177

Yafei Yuan, Chunmin Liu, Yaopeng Li, Jing Li

{"title":"Influence of Annealing Temperature Modulation on the Structural and Optical Properties of ZnSe Thin Films","authors":"Yafei Yuan, Chunmin Liu, Yaopeng Li, Jing Li","doi":"10.1002/crat.202000177","DOIUrl":"https://doi.org/10.1002/crat.202000177","url":null,"abstract":"The research work is devoted to study the influence of annealing temperature on the structural and optical properties of ZnSe thin films. The samples are prepared by a thermal evaporation technique and part of the as‐deposited films are annealed. X‐ray diffraction patterns and Raman spectra analysis reveal that the ZnSe thin films have cubic zinc‐blende crystal structure and the crystallinity increases as the annealing temperature increases. For the linear optical parameters, the absorption edge moves to shorter wavelengths with the increase of annealing temperature. Based on Swanepoel's method, the refractive index, film thickness, absorption coefficient and optical band gap are determined. The values of band gap are found to increase from 2.63 to 2.68 eV as the annealing temperature increases. By performing an open aperture Z‐scan technique with femtosecond pulses under 800 nm wavelength, all ZnSe samples show two‐photon absorption responses. It is found that the modulation depth and the two‐photon absorption coefficient decrease with increasing annealing temperature. Moreover, all samples exhibit better optical limiting responses at higher incident power intensities. These novel properties render this a promising material for traditional optoelectronic devices and optical limiters.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"94 12 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85276080","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}

引用次数: 0

Synthesis, Single‐Crystal Structure, Dielectric Properties of a New Phosphate K3Bi6.5(PO4)7.5 新型磷酸盐K3Bi6.5(PO4)7.5的合成、单晶结构和介电性能

IF 1.5 4区材料科学

Crystal Research and Technology Pub Date : 2021-03-22 DOI: 10.1002/crat.202000228

Chiraz Falah, Youssef Ben Smida, N. Sdiri, T. Soltani

引用次数: 1

Handling of Multiple‐Wave Effects in the Measurement of Forbidden X‐Ray Reflections in TeO2 TeO2中禁止X射线反射测量中的多波效应处理

IF 1.5 4区材料科学

Crystal Research and Technology Pub Date : 2021-03-22 DOI: 10.1002/crat.202000195

K. Kozlovskaya, A. Kulikov, D. Novikov, E. Ovchinnikova, A. M. Ustyugov, V. Dmitrienko

引用次数: 1

Synthesis of MoS2 Layers on GaN Using Ammonium Tetrathiomolybdate for Heterojunction Device Applications 用四硫钼酸铵在氮化镓上合成MoS2层的异质结器件

IF 1.5 4区材料科学

Crystal Research and Technology Pub Date : 2021-03-22 DOI: 10.1002/crat.202000198

P. Desai, Bhagyashri Todankar, A. Ranade, M. Kondo, Takehisa Dewa, M. Tanemura, G. Kalita

{"title":"Synthesis of MoS2 Layers on GaN Using Ammonium Tetrathiomolybdate for Heterojunction Device Applications","authors":"P. Desai, Bhagyashri Todankar, A. Ranade, M. Kondo, Takehisa Dewa, M. Tanemura, G. Kalita","doi":"10.1002/crat.202000198","DOIUrl":"https://doi.org/10.1002/crat.202000198","url":null,"abstract":"2D materials such as molybdenum sulfide (MoS2) integrated with conventional semiconductors lead to the fabrication of novel heterojunctions with pivotal electrical and optoelectronic properties. Herein, an approach is reported which addresses the growth of MoS2 crystals on the lattice‐matched Ga–polar gallium nitride (GaN) wafer using ammonium tetrathiomolybdate (ATM) as a precursor in a chemical vapor deposition (CVD) process, instead of using the molybdenum‐oxide‐based precursors. Unidirectional triangular MoS2 crystals and continuous film are obtained on the free‐standing Ga–polar GaN substrate. Further, the interface quality of the as‐synthesized MoS2 crystals and GaN wafer is explored by X‐ray photoelectron spectroscopy. It is observed that a good quality interface can be obtained by using the ammonia‐containing ATM precursor, where the surface oxygen at the interface is significantly less. A heterojunction device is fabricated with the synthesized MoS2 layer on GaN, showing excellent rectifying diode characteristics and a photovoltaic action with light illumination. This study reveals the suitability of the ammonia‐containing ATM precursor for the growth of MoS2 crystals on GaN in the CVD process to obtain a suitable heterostructure for device applications.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"24 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73935035","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}

引用次数: 1

Influence of Geometric Structure and Feeding Behavior of Casting on Freckle Formation during Directional Solidification of a Ni‐Based Single‐Crystal Superalloy 铸件几何结构和喂入行为对Ni基单晶高温合金定向凝固中雀斑形成的影响

IF 1.5 4区材料科学

Crystal Research and Technology Pub Date : 2021-03-22 DOI: 10.1002/crat.202000197

Dongyup Han, Weiguo Jiang, Jiu-han Xiao, Kai-wen Li, Yu-zhang Lu, L. Lou

{"title":"Influence of Geometric Structure and Feeding Behavior of Casting on Freckle Formation during Directional Solidification of a Ni‐Based Single‐Crystal Superalloy","authors":"Dongyup Han, Weiguo Jiang, Jiu-han Xiao, Kai-wen Li, Yu-zhang Lu, L. Lou","doi":"10.1002/crat.202000197","DOIUrl":"https://doi.org/10.1002/crat.202000197","url":null,"abstract":"Determining the effect of casting geometric structure on freckle formation is important in designing the directional solidification parameter of single‐crystal superalloy castings. In this research, single‐crystal castings of a third‐generation nickel (Ni)‐based superalloy with different thicknesses and structures are prepared by conventional Bridgman high‐rate‐solidification technique at withdrawal rates of 1, 3, and 6 mm min–1. The experimental results show that the freckles in castings with expansion structures are severer than those with contraction structures at a withdrawal rate of 1 mm min–1, and vice versa at withdrawal rates of 3 and 6 mm min–1. It is found that the larger casting thickness tends to promote the freckle formation at the same withdrawal rate. Furthermore, a lower tendency is displayed at the withdrawal rate of 3 mm min–1 in freckle formation, whereas an increased tendency is displayed at the withdrawal rate of 6 mm min–1. The different withdrawal rates, thicknesses, and structures of casting cause differences in cooling rate, shrinkage flow, and mushy zone morphology, which are believed to be responsible for the tendency of freckle formation.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"36 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80819407","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}

引用次数: 3

The Agglomeration of Niacin Crystals in the Cooling Crystallization Process 烟酸晶体在冷却结晶过程中的结块

IF 1.5 4区材料科学

Crystal Research and Technology Pub Date : 2021-03-22 DOI: 10.1002/crat.202000209

Lei Wang, Min Su

{"title":"The Agglomeration of Niacin Crystals in the Cooling Crystallization Process","authors":"Lei Wang, Min Su","doi":"10.1002/crat.202000209","DOIUrl":"https://doi.org/10.1002/crat.202000209","url":null,"abstract":"Crystal agglomeration is an important factor that can affect the purity and crystal habit of crystalline products. Agglomeration of niacin crystals in its cooling crystallization and its mechanism is investigated using both experimental and molecular dynamics simulation methods. The magnitude of the interaction energy which is mainly contributed by the hydrogen bond and π–π stacking between the (0 1 1) crystal face and (1 1 −1) crystal face that have both the pyridine and carboxyl groups is the main factor determining the extent of agglomeration of niacin crystal. Besides, the interaction energy increases with the crystallization temperature and the supersaturation of the solution, and hence the agglomeration is more severe. The change of solvent species has minimal effect on the agglomeration of crystals. Besides, the agglomeration situation of carbamazepine and acetaminophen that with similar structures to niacin is also verified using molecular dynamics simulations. The findings in this work can be used to predict, control the agglomeration phenomenon, and optimize the crystallization process of niacin and other substances with similar chemical structure.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"70 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85345454","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}

引用次数: 2

Investigation on the Growth and Properties of Six Garnet Single Crystals with Large Lattice Constants 六种大晶格常数石榴石单晶的生长与性能研究

IF 1.5 4区材料科学

Crystal Research and Technology Pub Date : 2021-03-22 DOI: 10.1002/crat.202000221

Zhiyuan Han, D. Sun, Huili Zhang, Jianqiao Luo, Cong Quan, Lunzhen Hu, Kunpeng Dong, M. Cheng, Guangzhu Chen, Y. Hang

{"title":"Investigation on the Growth and Properties of Six Garnet Single Crystals with Large Lattice Constants","authors":"Zhiyuan Han, D. Sun, Huili Zhang, Jianqiao Luo, Cong Quan, Lunzhen Hu, Kunpeng Dong, M. Cheng, Guangzhu Chen, Y. Hang","doi":"10.1002/crat.202000221","DOIUrl":"https://doi.org/10.1002/crat.202000221","url":null,"abstract":"Large lattice constant Y3Al5O12, Gd3Ga5O12 (GGG), Y3Sc2Ga3O12 (YSGG), Gd3Sc2Ga3O12, Ca0.4Mg0.25Zr0.65Gd2.6Ga4.1O12 (CaMgZr:GGG), and Gd1.17Y1.83Sc2Ga3O12 (GYSGG) substrate crystals with 2 in. in diameter are grown by the Czochralski (Cz) method, their physical, chemical, and optical properties are analyzed and compared in details. The X‐ray rocking curves (XRCs) illustrate that the as‐grown crystals possess high crystalline quality. The lattice constants of six crystals are calculated and that of GYSGG can be easily adjusted in the range of 1.2450–1.2565 nm by changing the Gd/Y proportion. The dislocation densities on the (111)‐crystalline face are about 102 cm−2 order of magnitude. The thermal conductivities of six crystals are measured to be 11.72, 8.98, 6.83, 5.45, 4.67, and 4.66 W m−1 K−1, respectively. It is found that the thermal expansion coefficients of six crystals can be reduced by annealing at 1273 K for 60 h. In addition, the transmission spectra show that the six crystals have excellent transparency and the coefficients of the Sellmeier equation are fitted by the calculated refractive indices. These results of the six crystals can provide the necessary parameters and references for the selection of suitable substrate materials or laser host crystals.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"67 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77284891","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}

引用次数: 12

Particle Size and Crystal Habit Modification of Active Pharmaceutical Ingredient Using Cooling Sonocrystallization: A Case Study of Probenecid 用冷却声结晶法改变活性药物成分的粒径和结晶习性——以苯丙酸为例

IF 1.5 4区材料科学

Crystal Research and Technology Pub Date : 2021-03-15 DOI: 10.1002/crat.202000182

Chun-Hao Chang, Chieh-Ming Hsieh, Chie-Shaan Su

{"title":"Particle Size and Crystal Habit Modification of Active Pharmaceutical Ingredient Using Cooling Sonocrystallization: A Case Study of Probenecid","authors":"Chun-Hao Chang, Chieh-Ming Hsieh, Chie-Shaan Su","doi":"10.1002/crat.202000182","DOIUrl":"https://doi.org/10.1002/crat.202000182","url":null,"abstract":"This study uses a cooling sonocrystallization process to recrystallize an active pharmaceutical ingredient, probenecid, and to improve the crystal qualities such as crystal habit and particle size characteristics. To screen the appropriate solvent system, solubility data of probenecid in organic solvent are measured, reported, and correlated by van't Hoff equation. According to the measured solubilities and data acquired from literature, sonocrystallization experiments using solvents with acceptable theoretical recovery are performed. Owing to the satisfactory throughput, yield, and crystal qualities, ethanol is finally decided as the appropriate solvent system. The effect of operating parameters in sonocrystallization including the solution concentration, sonication intensity, sonication duration, and cooling rate using ethanol as the solvent is further studied. With applying power ultrasound, probenecid crystals with narrow size distribution, regular crystal habit, and mean size around 15 µm are successfully produced. Finally, crystal form and spectroscopic property of sonocrystallized sample and probenecid as received from the supplier are compared and confirmed consistent from the analytical results of powder X‐ray diffractometer and Fourier transform infrared spectroscopy.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"4 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80675089","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}

引用次数: 2

Facile Hydrothermal Synthesis of EAB‐Type Zeolite under Static Synthesis Conditions 静态条件下易水热合成EAB型沸石

IF 1.5 4区材料科学

Crystal Research and Technology Pub Date : 2021-03-15 DOI: 10.1002/crat.202000163

T. Hagio, Jae-Hyeok Park, Yan Lin, Yanqin Tian, Y. Hu, Xinling Li, Y. Kamimoto, R. Ichino

{"title":"Facile Hydrothermal Synthesis of EAB‐Type Zeolite under Static Synthesis Conditions","authors":"T. Hagio, Jae-Hyeok Park, Yan Lin, Yanqin Tian, Y. Hu, Xinling Li, Y. Kamimoto, R. Ichino","doi":"10.1002/crat.202000163","DOIUrl":"https://doi.org/10.1002/crat.202000163","url":null,"abstract":"Conventionally, EAB‐type zeolites are crystallized by hydrothermal synthesis for many days under agitational synthesis conditions such as rotation or stirring. In the present study, EAB‐type zeolite is obtained by hydrothermal synthesis within 12 h under static synthesis conditions for the first time. The effects of crystallization temperature, aging of the precursor sol, and addition of seed crystals are investigated. The results reveal that EAB‐type zeolite can be obtained when using a precursor sol with short aging time followed by hydrothermal synthesis in a very narrow temperature range 110 °C−120 °C under static synthesis condition. Addition of seed crystals is found to suppress the formation of SOD‐type zeolite, the primary phase at high hydrothermal synthesis temperatures, while it does not increase the crystallization rate of EAB‐type zeolite. Furthermore, the crystallization behavior at 120 °C is examined by varying the synthesis time. EAB‐type zeolite with invariably twinned plate‐like morphology starts to crystallize between synthesis time of 3 to 6 h at 120 °C under the static synthesis condition.","PeriodicalId":10797,"journal":{"name":"Crystal Research and Technology","volume":"210 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75649946","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}

引用次数: 2