Crystals
·
2020
·Vol. 10
·期 8
·698
·
IF 2.404
Mengdi Fan,Guangda Wu,Fapeng Yu,Lili Li,Yanlu Li,Xiufeng Cheng,Xian Zhao
The bismuth layer-structured ferroelectrics (BLSFs) materials have potential for high-temperature piezoelectric applications. Among these piezoelectric materials, the CaBi4Ti4O15(CBT) piezoelectric ceramic with a high decomposition temperature of about 1250 °C attracts a lot of attention. Achieving a CBT single crystal is a significant way to improve its piezoelectric properties. For this purpose, the flux system for growing CBT crystal was explored in this study. The optimum flux composition ratio was found to be PbO:B2O3:CBT = 3:3:1 in mol%, where the PbO–B2O3mixtures were used as a flux system. Millimeter size flake-shaped CBT crystals were obtained using the spontaneous growth process for the first time. The relationship between the crystal structure and flake growth habit was analyzed. In addition, the bandgap was evaluated by the combination of transmittance spectrum and first-principle calculations. Besides, the piezoelectric property was predicted from the perspective of polyhedral distortion, which indicated the potential of CBT crystal for piezoelectric applications.Keywords:CaBi4Ti4O15;single crystal growth;flux method;dipole moments
研究领域:
材料科学
·
晶体学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2021
·Vol. 105
·期 3
·1954-1966
·
IF 3.784
Yu Wang,Kuo-Chih Chou,Guo-Hua Zhang
Due to strong anti-poisoning ability, good emission stability, high emission current density, lanthanum hexaboride (LaB 6 ) and cerium hexaboride (CeB 6 ) have been maturely applied in electron emission emitter. In this paper, a new manufacturing method for LaB 6 (or CeB 6 ) powder was proposed by using La 2 O 3 (or CeO 2 ), B 4 C, and Al as raw materials. After high-temperature reaction in the range of 1673–1773 K and the following alkaline leaching at 90°C, LaB 6 or CeB 6 powder with particle size of about 10 μm was obtained. Furthermore, by Al metal flux method, the obtained powder was used to manufacture single crystal block with size of several millimeters.
研究领域:
材料科学
·
电子发射材料
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2025
·
IF 6.4
Zhen-Cheng Wu,Fang-Xu Tian,Rui Xiao,Mao-Yin Ran,Wenlong Liu,Wen-Tong Chen,Sheng-Ping Guo
The study of infrared nonlinear optical (NLO) materials with wide band gaps and high laser induced damage thresholds (LIDTs) is an urgent and challenging topic. Here, we report the NLO properties of CsRESiS4 (RE = Sm, Gd–Ho), which were synthesized by the reactive flux CsCl assisted RExOy–B–S routine. The structure of CsRESiS4, [CsS7] pentagonal bipyramids are orderly arranged to populate the interlayer space created by [RES7] monocapped triangular prisms consolidated [SiS4] tetrahedra. They all exhibit wide band gaps of 3.51–3.95 eV, high LIDTs of 3.6–5.5 × AGS, and NLO activity, with CsHoSiS4 possessing the largest band gap among rare-earth chalcogenides. The theoretical calculation results indicate that [RES7] monocapped triangular prisms are the main source of NLO activity and have a wide band gap. This work provides an effective case for exploring wide band gap infrared NLO materials.
研究领域:
材料科学
·
凝聚态物理
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无机化学
·
光学材料
·
功能晶体
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2023
·
IF 8.4
Hongju Qiu,Yanqiong Zhang,Weiwei Huang,Jinhui Peng,Jin Chen,Lei Gao,Mamdouh Omran,Nan Li,Guo Chen
Tetragonal zirconia nanopowders (3Y-TZP NPs) stabilized by 3 mol % Y2O3 were synthesized by a novel sol–gel–flux method. The effects of calcination temperature, Y2O3 content, and molten salt system (NaCl + KCl binary system and NaCl unary system) on the phase composition and morphology of nanopowders (NPs) were investigated. Meanwhile, the sintering properties of the prepared 3Y-TZP NPs were studied. The 3Y-TZP NPs and sintered ceramics were characterized by thermogravimetry-differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) analysis, and X-ray fluorescence (XRF) spectroscopy. The results show that the optimum calcination temperature for obtaining dispersed ZrO2 NPs is reduced from 800 to 660 °C when the NaCl unary system is substituted by the NaCl + KCl binary system. 3Y-TZP NPs with a single tetragonal phase are obtained in the NaCl + KCl binary system when Y2O3 content in the raw material is 5 mol %. The average particle size of the obtained ZrO2 NPs is reduced from 47.25 nm in the unary system to 26.18 nm in the binary system because of the lower calcining temperature. Furthermore, the 3Y-TZP NPs obtained in the binary system have narrower particle size distribution and better sintering performance than ZrO2 NPs obtained in the unary system. After sintering for 4 h at 1200 °C, the former generated 3Y-TZP ceramics with higher density and finer grain size. This work produced narrow-distributed well-dispersed 3Y-TZP NPs with quasi-spherical morphology, which are good candidates for the applications, including oxygen sensors and thermal barrier coatings.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Nan Li,Hongju Qiu,Lei Gao,Zhipeng Xie,Yunlong He,Yan Jiang,Guo Chen
Herein, to alleviate the hard agglomeration of ZrO 2 nanoparticles (NPs) fabricated by the traditional sol-gel method (SGM), a novel sol-gel-flux method (SGFM) is applied to tailor ZrO 2 nanoparticles (NPs) stabilized by 5 mol% Y 2 O 3 (5Y–ZrO 2 ) by in situ introduction of NaCl NPs among xerogel particles. The phase composition, micromorphology, surface area, and sintering performances of 5Y–ZrO 2 products fabricated by SGM and SGFM are compared. The effects of calcination temperature on the phase composition, micromorphology, and particle size of 5Y–ZrO 2 products prepared by SGFM are systematically investigated. The results show that the 5Y–ZrO 2 particles prepared by SGM are severely agglomerated and irregular, while the 5Y–ZrO 2 NPs prepared by SGFM are well dispersed, uniformly distributed, and quasispherical. The former can hardly be densified by sintering, while the latter shows excellent sintering performance. By sintering 5Y–ZrO 2 NPs prepared by SGFM at 1200 °C for 3 h, 5Y-TZP with a high density and an average grain size of 0.29 μm is fabricated. The in situ generated NaCl particles effectively separate ZrO 2 particles during sintering. The calcination temperature plays a crucial role in controlling the phase composition, agglomeration degree, micromorphology, particle size distribution , and particle size of 5Y–ZrO 2 products synthesized by SGFM, and the optimal calcination temperature is suggested to be 790 °C.
研究领域:
材料科学
·
纳米技术
·
陶瓷
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2025
·Vol. 54
·期 30
·11601-11606
·
IF 3.3
Guansong Zheng,Wang Zhao,Xiaoyu Wu,Hongshan Wang,Yinxia Du,Juanjuan Lu,Xiao-dong Zhou,Junjie Li
Chalcohalides, combining the structural and property advantages of chalcogenides and halides, have been demonstrated to be a promising system for the design of advanced photoelectric functional materials. Herein, a new chalcohalide compound, Cs9Si8Se20Cl, has been rationally designed by introducing a nonlinear optical (NLO)-active [Si4Se10] T2-supertetrahedral unit into a halide system and synthesized experimentally by the flux method with CsCl as the flux. The compound is composed of [CsSe7Cl] polyhedral, [CsSe6] octahedral, and [Si4Se10] T2-supertetrahedral units. To the best of our knowledge, the [CsSe7Cl] mixed anionic unit appears for the first time in the compound, and the rare [Si4Se10] T2-supertetrahedral unit has been demonstrated to be a potential NLO-active unit for the design of infrared NLO materials with balanced optical properties. The theoretical calculations uncovered that the strong orbital hybridization between Si-3p, Se-4p and Cl-3p orbitals results in a wide band gap of 3.075 eV in the title compound. The results enrich the structural diversity of chalcohalide compounds and provide valuable insights into the design of wide band gap selenides.
研究领域:
材料化学
·
无机化学
·
光学材料
·
固态化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）