Journal of Crystal Growth最新文献

Role of synthesis temperature in the formation of ZnO nanoparticles via the Sol-Gel process 合成温度在通过溶胶-凝胶工艺形成氧化锌纳米粒子中的作用

IF 1.7 4区材料科学

Journal of Crystal Growth Pub Date : 2024-11-15 DOI: 10.1016/j.jcrysgro.2024.128003

A. Modrić-Šahbazović , A. Smajlagić , Z. Sakić , M. Novaković , N. Latas , M. Popović , M. Đekić , S. Isaković , A. Salčinović Fetić

{"title":"Role of synthesis temperature in the formation of ZnO nanoparticles via the Sol-Gel process","authors":"A. Modrić-Šahbazović , A. Smajlagić , Z. Sakić , M. Novaković , N. Latas , M. Popović , M. Đekić , S. Isaković , A. Salčinović Fetić","doi":"10.1016/j.jcrysgro.2024.128003","DOIUrl":"10.1016/j.jcrysgro.2024.128003","url":null,"abstract":"<div><div>This study examines the synthesis of ZnO powder via the sol–gel method at temperatures of 25 °C and 60 °C. Characterization was conducted using standard techniques to investigate how these temperature conditions influence the physicochemical properties of the resulting material. XRD analysis confirmed high crystallinity with a pure hexagonal wurtzite structure, with average crystallite sizes of approximately 20 nm at 25 °C and 38 nm at 60 °C. Both SEM and TEM techniques established needle-like nanorods at 25 °C and nanoflower-like structures at 60 °C. Analyzing the high-resolution XPS spectra of the Zn2p and O1s photoelectron lines revealed a predominant Zn(II) state, with the contribution of ZnO increasing from 14.6 at.% to 41.6 at.% at higher temperatures. This change was accompanied by a decrease in defective oxygen and water content. Furthermore, DSC analysis revealed significant differences in thermal properties of ZnO powders synthesized at 25 °C and 60 °C, with distinct endothermic peaks around 120 °C corresponding to the evaporation of the solvent used in the synthesis process. The energy required for phase transitions was notably higher for the 25 °C synthesis, indicating greater thermal stability and energy demands compared to the 60 °C synthesis.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"650 ","pages":"Article 128003"},"PeriodicalIF":1.7,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652409","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

Thermal atomic layer deposition of Ga2O3 films using trimethylgallium and H2O 使用三甲基镓和 H2O 的热原子层沉积 Ga2O3 薄膜

IF 1.7 4区材料科学

Journal of Crystal Growth Pub Date : 2024-11-12 DOI: 10.1016/j.jcrysgro.2024.127974

Chufeng Hou , Kai Liang , Ziyu Yang , Qiang Wang , Yuefei Zhang , Fei Chen

{"title":"Thermal atomic layer deposition of Ga2O3 films using trimethylgallium and H2O","authors":"Chufeng Hou , Kai Liang , Ziyu Yang , Qiang Wang , Yuefei Zhang , Fei Chen","doi":"10.1016/j.jcrysgro.2024.127974","DOIUrl":"10.1016/j.jcrysgro.2024.127974","url":null,"abstract":"<div><div>The Atomic Layer Deposition (ALD) technique is regarded as an effective method for fabricating high-quality Ga<sub>2</sub>O<sub>3</sub> thin films. Trimethyl gallium (TMG), with its high vapor pressure at room temperature (227 Torr), is widely utilized as a gallium precursor in this technique. For oxygen precursors, common choices include O<sub>3</sub> and O<sub>2</sub> plasma. However, the impact of H<sub>2</sub>O as an oxygen precursor on Ga<sub>2</sub>O<sub>3</sub> thin films during Thermal Atomic Layer Deposition (TALD) remains insufficiently explored. This study investigates the temperature window and growth characteristics of Ga<sub>2</sub>O<sub>3</sub> thin films, deposited using TMG and H<sub>2</sub>O as precursors, on sapphire substrates within the temperature range of 250–500 °C. At 250 °C, deposited Ga<sub>2</sub>O<sub>3</sub> films exhibit an amorphous structure, whereas within the 300–500 °C substrate temperature range, they transition to the α-phase. The half-peak width (FWHM) narrows as the temperature increases, with characteristic peaks of the (0006) facets shifting to higher angles at 500 °C. STEM analysis reveals complete coherence between α-Ga<sub>2</sub>O<sub>3</sub> films and the sapphire substrate, indicating a pseudo-crystalline structure formation. The growth rate of the films at 450 °C is 0.083 Å/cycle. Ga<sub>2</sub>O<sub>3</sub> films prepared with H<sub>2</sub>O as the oxygen precursor exhibit Ga-rich properties, with (Ga + Al)/O atomic ratios between 0.88 and 0.91 across the 250–500 °C temperature range. The films’ roughness (Ra) ranges from 0.453 to 0.646 nm. Island-like particles form on the film surface within the 400–500 °C range, smoothing out as the temperature rises. The film’s band gap peaks at 5.50 eV at 450 °C. The reaction of TMG with H<sub>2</sub>O on sapphire substrates yields Ga<sub>2</sub>O<sub>3</sub> films and CH<sub>4</sub> by-products, akin to the trimethylaluminum process.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"650 ","pages":"Article 127974"},"PeriodicalIF":1.7,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652408","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

Doping behavior and occurrence state of Na impurity in α-calcium sulfate hemihydrate prepared in Na2SO4 solution 在 Na2SO4 溶液中制备的α-半水硫酸钙中 Na 杂质的掺杂行为和发生状态

IF 1.7 4区材料科学

Journal of Crystal Growth Pub Date : 2024-11-10 DOI: 10.1016/j.jcrysgro.2024.127993

Lusong Wang , Xianbo Li , Yuqi He , Hu Huang , Yawen Du

引用次数: 0

Quantum chemical study of trimethylindium and trimethylgallium gas-phase reaction pathways in InGaN MOCVD growth 对 InGaN MOCVD 生长过程中三甲基铟和三甲基镓气相反应途径的量子化学研究

IF 1.7 4区材料科学

Journal of Crystal Growth Pub Date : 2024-11-07 DOI: 10.1016/j.jcrysgro.2024.127992

Zhigang Lu , Jianfeng Pan , Hong Zhang , Chao Jiang , Wenming Yang

{"title":"Quantum chemical study of trimethylindium and trimethylgallium gas-phase reaction pathways in InGaN MOCVD growth","authors":"Zhigang Lu , Jianfeng Pan , Hong Zhang , Chao Jiang , Wenming Yang","doi":"10.1016/j.jcrysgro.2024.127992","DOIUrl":"10.1016/j.jcrysgro.2024.127992","url":null,"abstract":"<div><div>Density functional theory was used to analyze the formation of InGaN from trimethylindium (TMIn) and trimethylgallium (TMGa) by metalorganic chemical vapor deposition in ammonia in terms of the reaction between trimethyl compounds and NH<sub>3</sub>, as well as the subsequent reactions of the key amino species DMInNH<sub>2</sub>. The calculation model is established in GAUSSIAN 09, and the results obtained by the calculation model are proved to be reliable by comparing with the previous research results. Reaction pathways were assumed and the Gibbs free energy and activation free energy calculation were conducted at different temperatures. TMIn and TMGa can undergo adduct reactions with the first NH<sub>3</sub> molecule at reaction temperatures below 596 K and 465 K, respectively, but they cannot further react with the second NH<sub>3</sub> molecule to form additional products. The temperature range for adduct reactions between TMIn and NH<sub>3</sub> is wider compared to TMGa and NH<sub>3</sub>. In the absence of H radicals in the reaction chamber, DMInNH<sub>2</sub> does not undergo spontaneous CH<sub>3</sub> radical elimination reactions or CH<sub>4</sub> elimination reactions. Instead, DMInNH<sub>2</sub> is more inclined to undergo dimerization reactions and CH<sub>4</sub> elimination reactions with NH<sub>3</sub>, leading to the formation of subsequent products, In(NH<sub>2</sub>)<sub>3</sub> and dimers. However, in the presence of H radicals in the reaction chamber, H radicals can facilitate the CH<sub>3</sub> radical elimination reaction of DMInNH<sub>2</sub> and also promote the NH<sub>2</sub> radical elimination reaction of In(NH<sub>2</sub>)<sub>3,</sub> In(NH<sub>2</sub>)<sub>2</sub> and InNH<sub>2</sub>, enabling these reactions to occur spontaneously within the studied temperature range. Consequently, the subsequent products of DMInNH<sub>2</sub> become indium atoms and dimers.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"650 ","pages":"Article 127992"},"PeriodicalIF":1.7,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652406","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

Characterization and mid-infrared laser operation in Er:CaF2 single crystal fiber grown by the laser heated pedestal growth method 用激光加热基座生长法生长的 Er:CaF2 单晶光纤的特性和中红外激光器工作原理

IF 1.7 4区材料科学

Journal of Crystal Growth Pub Date : 2024-11-06 DOI: 10.1016/j.jcrysgro.2024.127991

Xu Wu, Zhen Zhang, Yunfei Wang, Shaochen Liu, Zhonghan Zhang, Liangbi Su, Anhua Wu

{"title":"Characterization and mid-infrared laser operation in Er:CaF2 single crystal fiber grown by the laser heated pedestal growth method","authors":"Xu Wu, Zhen Zhang, Yunfei Wang, Shaochen Liu, Zhonghan Zhang, Liangbi Su, Anhua Wu","doi":"10.1016/j.jcrysgro.2024.127991","DOIUrl":"10.1016/j.jcrysgro.2024.127991","url":null,"abstract":"<div><div>Er:CaF<sub>2</sub> crystal, characterized by low doping and high efficiency, is a suitable material for single-crystal fiber (SCF). 3 at.% Er:CaF<sub>2</sub> SCFs were grown using the laser heated pedestal growth (LHPG) method. Significant oxidation-induced whitening phenomena were observed during growth. Increasing the growth rate helped mitigate further deterioration due to oxidation. This is likely because higher growth speeds allow the SCF to quickly move away from temperature ranges conducive to oxidation. As oxidation progressed, the phonon energy of 3 at.% Er:CaF<sub>2</sub> SCF increased, causing the emission intensity at ∼ 1 μm to decrease from 77 % in the initial source rod to 6 % in the fully whitened state. Additionally, the lifetime of the <sup>4</sup>I<sub>11/2</sub> level decreased by approximately 10 times, from 8.988 ms to 0.822 ms. Continuous laser output at ∼ 2.8 μm was achieved using the transparent portion of 3 at.% Er:CaF<sub>2</sub> SCF. With an output mirror transmission of 2 %, a maximum output power of 251 mW and a slope efficiency of 15.9 % were obtained. The laser experiment demonstrated the potential application of LHPG-grown Er:CaF<sub>2</sub> SCF in ∼ 2.8 μm lasers, but further performance enhancement requires additional strategies to address oxidation issues. This work provides valuable insights into the growth of Er:CaF<sub>2</sub> SCF using the LHPG method.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"650 ","pages":"Article 127991"},"PeriodicalIF":1.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652405","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

Origin of giant dielectric constant in Ta+Gd co-doped TiO2 single crystals by optical traveling floating zone method 用光学行进浮动区法研究掺杂 Ta+Gd 的 TiO2 单晶中巨型介电常数的起源

IF 1.7 4区材料科学

Journal of Crystal Growth Pub Date : 2024-11-06 DOI: 10.1016/j.jcrysgro.2024.127990

Jiangtao Fan , Zhanggui Hu , Yicheng Wu

{"title":"Origin of giant dielectric constant in Ta+Gd co-doped TiO2 single crystals by optical traveling floating zone method","authors":"Jiangtao Fan , Zhanggui Hu , Yicheng Wu","doi":"10.1016/j.jcrysgro.2024.127990","DOIUrl":"10.1016/j.jcrysgro.2024.127990","url":null,"abstract":"<div><div>The co-doped TiO<sub>2</sub> polycrystalline ceramics have dramatic dielectric behavior (>10<sup>4</sup>), but its source is still not completely clarified. Compared to ceramic materials, single crystals can maintain most of the original properties of the material and eliminate the grain boundary and pore interferences, thus facilitating the exploration of the source of the dielectric properties. Here, we chose Gd<sup>3+</sup> with a moderate ionic radius as the acceptor ion and Ta<sup>5+</sup> as the donor, preparing (Gd<sub>0.5</sub>Ta<sub>0.5</sub>)<sub>0.01</sub>Ti<sub>0.99</sub>O<sub>2</sub> single crystals by the optical traveling floating zone method to investigate giant dielectric properties. It was found that a dielectric constant (<em>ε</em>′ ∼1.5 × 10<sup>4</sup>), and a dielectric loss (tanδ ∼ 0.07) were achieved simultaneously in (Gd<sub>0.5</sub>Ta<sub>0.5</sub>)<sub>0.01</sub>Ti<sub>0.99</sub>O<sub>2</sub> single crystals at 10<sup>5</sup>Hz. Electrochemical impedance spectroscopy and XPS analyses indicate that the high dielectric properties are mainly attributed to electrons pinning defective dipoles clusters. In addition, dielectric relaxation behavior under DC bias suggests that electrode effects also affect the dielectric constant. This study provides insights for the origin of the large dielectric constant and the growth of single crystals in TiO<sub>2</sub>-based materials.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"650 ","pages":"Article 127990"},"PeriodicalIF":1.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652416","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

High-quality InAs homoepitaxial layers grown by molecular beam epitaxy 通过分子束外延生长的高质量砷化镓同外延层

IF 1.7 4区材料科学

Journal of Crystal Growth Pub Date : 2024-11-05 DOI: 10.1016/j.jcrysgro.2024.127989

Hao Zhou , Yiqiao Chen , Chang Liu

{"title":"High-quality InAs homoepitaxial layers grown by molecular beam epitaxy","authors":"Hao Zhou , Yiqiao Chen , Chang Liu","doi":"10.1016/j.jcrysgro.2024.127989","DOIUrl":"10.1016/j.jcrysgro.2024.127989","url":null,"abstract":"<div><div>The growth conditions for InAs homoepitaxy by molecular beam epitaxy were comprehensively studied across a broad spectrum of substrate temperatures, As2/In flux ratios, and growth rates. It was found that the surface morphology and overall quality of the InAs layers were significantly influenced by these parameters. Optimal conditions, including a lower growth temperature, reduced As2 flux, and slower growth rate, were pivotal in achieving high-quality InAs layers. Two primary characterization techniques, differential interference contrast microscopy and atomic force microscopy, were employed to evaluate the material quality. High-quality InAs homoepitaxial layers were successfully grown at a substrate temperature of 455 °C and a growth rate of 0.33 monolayers per second (ML/s). These layers exhibited a remarkably low defect density of approximately 300 defects per square centimeter, which is over an order of magnitude lower than previously reported, and a notably low root-mean-square roughness of 0.116 nm. At a growth rate of 0.33 ML/s, the growth temperature range for InAs homoepitaxial layers was found to be quite broad, whereas the As2/In flux ratio remained within a narrow range. This study underscores the critical role of precise control over growth parameters in the molecular beam epitaxy process for producing high-quality InAs homoepitaxial layers.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"650 ","pages":"Article 127989"},"PeriodicalIF":1.7,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652461","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

Eco-Friendly ZnO/CuO/Ni Nanocomposites: Enhanced photocatalytic dye adsorption and hydrogen evolution for sustainable energy and water purification 生态友好型 ZnO/CuO/Ni 纳米复合材料：增强光催化染料吸附和氢进化，实现可持续能源和水净化

IF 1.7 4区材料科学

Journal of Crystal Growth Pub Date : 2024-11-05 DOI: 10.1016/j.jcrysgro.2024.127984

Souhaila Meneceur , Salah Eddine Laouini , Hamdi Ali Mohammed , Abderrhmane Bouafia , Chaima Salmi , Johar Amin Ahmed Abdullah , Fahad Alharthi

{"title":"Eco-Friendly ZnO/CuO/Ni Nanocomposites: Enhanced photocatalytic dye adsorption and hydrogen evolution for sustainable energy and water purification","authors":"Souhaila Meneceur , Salah Eddine Laouini , Hamdi Ali Mohammed , Abderrhmane Bouafia , Chaima Salmi , Johar Amin Ahmed Abdullah , Fahad Alharthi","doi":"10.1016/j.jcrysgro.2024.127984","DOIUrl":"10.1016/j.jcrysgro.2024.127984","url":null,"abstract":"<div><div>Nanomaterials and nanocomposites, known for their unique properties, are increasingly vital in diverse fields such as energy and environmental remediation. This study presents biogenically synthesized ZnO/CuO/Ni nanocomposites using <em>Mentha Pulegium L.</em> leaf extract. The investigation focuses on their applications in photocatalytic dye adsorption and hydrogen evolution. Characterization via XRD, FTIR spectroscopy, SEM, and UV–visible spectroscopy confirms the nanocomposites’ semiconducting nature with a narrow bandgap energy of 2.46 eV. Structural analysis reveals cubic crystal structures with an average crystallite size of 29.1 nm. Under solar irradiation, the nanocomposites exhibit exceptional photocatalytic activity, degrading 99 % of 4-BP and 98 % of TB. Moreover, they achieve a notable hydrogen evolution rate of 5.79 mmol/g over six hours. These results underscore the efficacy of ZnO/CuO/Ni nanocomposites as catalysts for sustainable energy and water purification. Employing <em>Mentha Pulegium L.</em> extract for environmentally friendly synthesis enhances their photocatalytic properties, offering a cost-effective route to sustainable energy and clean water technologies.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"650 ","pages":"Article 127984"},"PeriodicalIF":1.7,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652459","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

Advances in defect characterization techniques using polarized light observation in SiC wafers for power devices 利用偏振光观测功率器件碳化硅晶片缺陷表征技术的进展

IF 1.7 4区材料科学

Journal of Crystal Growth Pub Date : 2024-11-05 DOI: 10.1016/j.jcrysgro.2024.127982

Shunta Harada , Kenta Murayama

引用次数: 0

“Catalyzed” nucleation: A critical review of proposed theories "催化 "成核：对拟议理论的批判性审查

IF 1.7 4区材料科学

Journal of Crystal Growth Pub Date : 2024-11-04 DOI: 10.1016/j.jcrysgro.2024.127973

Rasmus A.X. Persson

{"title":"“Catalyzed” nucleation: A critical review of proposed theories","authors":"Rasmus A.X. Persson","doi":"10.1016/j.jcrysgro.2024.127973","DOIUrl":"10.1016/j.jcrysgro.2024.127973","url":null,"abstract":"<div><div>In industrial-scale crystallization, secondary nucleation is the most important type of nucleation. In most cases, this phenomenon can be adequately explained as the result of mechanical forces that break existing crystallites apart, the strength of the effect being a smooth function of supersaturation and stirring vigor. However, in some special cases, crystallites of other polymorphs appear and/or no nucleation occurs except at a catastrophic rate above a supersaturation threshold, mimicking primary nucleation. In this paper, we review published theories for this latter type of secondary nucleation, for which we find contradicting explanations in the literature. We divide these explanations into two broad classes, depending on whether the secondary nucleation is mediated through local deviations of the bulk thermodynamic state variables (indirect effects) or directly through the interaction energy of the surface and growth units (direct effects). We argue that theoretical explanations of the second type are insufficient and while we can find no conclusive and theoretically consistent explanation for this well-established experimental phenomenon, it is hoped that this review will stimulate further research into this puzzle.</div></div>","PeriodicalId":353,"journal":{"name":"Journal of Crystal Growth","volume":"650 ","pages":"Article 127973"},"PeriodicalIF":1.7,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142652414","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