CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Lianshi Qu,Zhihao Zhao,Zhenyuan Li,Rao Zhang
MXene is a novel two-dimensional nano material with exceptional performance, which can be applied in the fields of energy storage structural materials, optics, catalysis, and sensors etc. However, its synthesis is a challenge to date. From the perspective of environmental friendliness, the method of Lewis salt etching can effectively avoid the use of dangerous reagents and has been seen as a pollution-free economic approach. In this article ZnCl 2 molten salt was chosen as corrosive agent to etch Ti 3 AlC 2 MAX phase and investigated the synthesis mechanism of Ti 3 C 2 Cl x MXene. The influence of main process factor, like raw materials, sintering temperature , and holding time on synthesis product were studied and discussed. The synthesis route was investigated by XRD and thermal analysis. SEM and TEM technology was used to analyze the microstructure and lattice of synthesis product. The results showed that the optimal process conditions: the molar ratio of raw materials was 1:6 (Ti 3 AlC 2 : ZnCl 2 ), the synthesis temperature and holding time were 600～700 °C and 4 h, respectively. Ti 3 C 2 Cl x MXene material prepared by this method has a complete layered structure and uniform composition, and its synthesis mechanism can be concluded to two steps: the first step was the reaction between Ti 3 AlC 2 MAX phase and ZnCl 2 to generate Ti 3 ZnC 2 MAX phase; In the second step, the Ti 3 ZnC 2 MAX phase reacted with the remaining ZnCl 2 to generate Ti 3 C 2 Cl x MXene material.
研究领域:
材料科学
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纳米技术
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DOI
高影响因子
Nanoscience and Nanotechnology Letters
·
2015
·Vol. 7
·期 5
·398-401
·
IF 1.431
Wang Shanshan,Zhang Jun,Peng Feng,Shao Lexi
Micron-sized Cu2FeSnS4 single crystals were synthesized by molten salt method using CuS, FeS and SnS as raw materials and using CsCl as fluxing agent for the first time. The Cu2FeSnS4 single crystals were investigated by X-ray diffraction,
Raman, X-ray photoelectron spectroscopy and UV-vis absorbance spectroscopy. The results showed that the Cu2FeSnS4 single crystals were having stannite structure with an average size about 50–100 μm and the band gap was about 1.45 eV.
研究领域:
材料科学
·
化学
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DOI
高影响因子
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
·
2019
·Vol. 34
·期 2
·299-302
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IF 0.605
Yan Ming,Yang Lei,Li Chao,Zou Yunqi
We prepared a two-dimensional transition metal carbide Ti 2 CT x by treatment of Ti2AlC in molten fluoride salt. Two fluorinated salt systems were used to etch Al from Ti 2 AlC powder precursor under the argon atmosphere, and then the resulting MXene was delaminated with TBAOH to produce few-layered nanosheets of Ti 2 CT x . The reaction was undergone at different temperatures to study the effect of temperature. The results show that the optimal reaction temperature is 600 °C in LiF-NaF-KF system, and 850 °C in NaFKF system. The molten salt treated products are delaminated and quasi-2D MXene sheets can be obtained. The thickness of the MXene sheets prepared from the binary molten salt system is smaller than that of the ternary molten salt system.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2024
·
IF 4.7
Lijiao Zhong,Xing Li,Yiquan Zhan,Yongsheng Liu,Kai Yang,Jinbiao Liu,Shiyong Liu,Junzhe Jiang,Liqing Li,Yoshihisa Sakata
Solar-driven hydrogen production through water splitting is currently one of the research hotspots nowadays. Lanthanum titanate (La 2 Ti 2 O 7 ) is one kind of layered-structure perovskite photocatalyst and possesses a superior electronic structure for photocatalytic overall water splitting. However, it suffers from several drawbacks, such as poor photo absorption and easy recombination of photogenerated charge carriers. In this study, sodium (Na) ion-doped La 2 Ti 2 O 7 with plate-like crystal morphology was synthesized by using molten salt synthesis (MSS). The XRD and TEM results indicated that the MSS method enhanced the crystallinity of La 2 Ti 2 O 7 . UV-vis, Raman and EPR spectra disclosed that Na doping through MSS introduced oxygen vacancies. The Na (0.3 mol%)-doped La 2 Ti 2 O 7 (MSS) provided the optimal hydrogen evolution rate, and the value was 6.43 times greater than that of pure La 2 Ti 2 O 7 synthesized by traditional solid-state reaction method. The synergistic effect of crystal facet engineering and defect engineering remarkably enhanced the photocatalytic activity of La 2 Ti 2 O 7 .
研究领域:
材料科学
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能源科学
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DOI
高影响因子
International Journal of Minerals Metallurgy and Materials
·
2020
·Vol. 27
·期 12
·1703-1710
·
IF 1.713
Zhou Jing,Nie Dan-dan,Jin Xian-bo,Xiao Wei
Pyrolysis of the Ta 2 O 5 /melamine mixture in molten chlorides is herein demonstrated as a facile and controllable method to nitridize and functionalize Ta 2 O 5 . The influence of the stoichiometry and composition of Ta 2 O 5 /melamine in molten salts on the nitridation process is rationalized to ensure the controllable preparation of Ta 3 N 5 and Ta 3 N 5 /TaON. The characterization results, including scanning electron microscopy, transmission electron microscopy, elemental mapping, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy, all confirm the existence of the Ta 3 N 5 /TaON heterojunction, in which the TaON nanoparticles are closely anchored to the Ta 3 N 5 nanorods. Benefiting from its composition and structure, the Ta 3 N 5 /TaON composites show enhanced photocatalytic activity for the degradation of methylene blue. The present study highlights that the molten salt method using a solid nitrogen source can be a new technique for rationalizing the design of nitrides and oxynitrides.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2013
·
IF 1.913
Jintai Lin,Zhan Zhou,Qianming Wang
GdNbO 4 :Eu 3+ and LuTaO 4 :Eu 3+ have been successfully prepared with different fluxes (NaCl, KCl, NaCl and KCl) by the molten salt method. X-ray diffraction (XRD) patterns illustrated that well crystallized GdNbO 4 :Eu 3+ and LuTaO 4 :Eu 3+ in the presence of fluxes were formed under reduced temperature (900 °C) in contrast to conventional method (GdNbO 4 :Eu 3+ : around 1200 °C; LuTaO 4 :Eu 3+ : around 1500 °C). Scanning electron microscope (SEM) images revealed that well dispersed particles were achieved (granular or rod-like structures). Meanwhile, the photo-luminescent studies demonstrated that both niobate and tantalate are efficient hosts to sensitize europium red emissions. The results indicated that GdNbO 4 :Eu 3+ using NaCl as the flux gave much enhanced red emission whereas LuTaO 4 :Eu 3+ synthesized with the assistance of mixed salts (NaCl–KCl) achieved the best luminescence.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2016
·
IF 2.322
Xin Liu,Junzhe Jiang,Yushuai Jia,Ailing Jin,Xiangshu Chen,Fei Zhang,Hongxian Han
Pure phase, regular shape and well crystallized nanorods of p-type semiconductor CaFe 2 O 4 have been fabricated for the first time by a facile molten salt assisted method, as confirmed by XRD , TEM, SEM and HRTEM. UV−vis diffuse reflectance spectra and Mott–Schottky plots show that the band structure of the CaFe 2 O 4 nanorods is narrower than that of the CaFe 2 O 4 nanoparticles synthesized by conventional method. The enhancement of the visible-light absorption is due to narrowness of the band gap in CaFe 2 O 4 nanorods. The appropriate ratio between the molten salt and the CaFe 2 O 4 precursors plays an important role in inhibiting the growth of the crystals along the (201) plane to give the desired nanorod morphology. This work not only demonstrates that highly pure p-type CaFe 2 O 4 semiconductor with tunable band structure and morphology could be obtained using the molten salt strategy, but also affirms that the bandgap of a semiconductor may be tunable by monitoring the growth of a particular crystal plane. Furthermore, the facile eutectic molten salt method developed in this work may be further extended to fabricate some other semiconductor nanomaterials with a diversity of morphologies.
研究领域:
材料科学
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半导体物理
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Rui Jia Liu,Ling Xu Yang,Ying Wang,Hui Jun Liu,Sheng Long Zhu,Chao Liu Zeng
High-purity ternary layered carbide V 2 AlC powders have been prepared by a two-step modified molten salt method, i.e. by firstly synthesizing V 2 C with V and C powders at 900 °C, followed by preparing V 2 AlC with V 2 C and Al powders as reactants at 900–950 °C in molten (Na,K)Cl. The average particle distribution of V 2 AlC powders was estimated to be ~400 nm. Molten salt as a reaction medium could promote the synthesis of V 2 C and V 2 AlC at lower temperatures. The synthesizing mechanisms of V 2 C and V 2 AlC in molten salts have also been discussed.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Jiahui Ma,Ning Xu,Yuxin Luo,Qi Liu,Yongping Pu
Ceria is widely used in industrial fields due to its unique chemical properties. In this work, a series of CeO 2 particles with controllable morphology, size, and defect concentration were obtained by a simple molten salt method. The adjustment of temperature and molten salt concentration has a considerable effect on the morphology and particle size of the final CeO 2 particles while prolonging the holding time has little effect. Ion doping and reducing atmosphere calcination were used to regulate the defect concentration to improve the chemical activity of CeO 2 particles. SEM results show that the morphology of CeO 2 particles transforms from sphere to octahedron under the two treatments. The Rietveld refinement results and the XPS spectra indicate that increasing calcination temperature, reducing atmosphere calcination and ion doping are beneficial to improving the oxygen vacancies and Ce 3+ concentration of CeO 2 samples, which are the reason for enhancing the photocatalytic activity of the samples. Moreover, the oriented attachment, agglomeration and merging of crystals formed by the decomposition of cerium precursors are the key to the growth of CeO 2 particles. Aggregates with exposed low-energy planes merge directly to form particles of various morphologies to maintain their own low energy.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2024
·Vol. 26
·期 10
·1418-1429
·
IF 2.6
Jun Liao,Sihao Ye,Xupeng Zhu,Wenfeng Fu,Shuwen Xue,Jing Qi,Jun Zhang
Kesterite Cu2ZnSnS4 (CZTS) is considered as one of the most promising thin-film solar cell and photocatalytic materials; however, its efficiency in practical photoelectric applications is often seriously limited by the presence of large numbers of Cu–Zn antisite defects. Alloying with Ag to fabricate Ag-alloyed CZTS ((AgxCu1−x)2ZnSnS4, ACZTS) can reduce the Cu–Zn antisite defects in CZTS, but few research studies have been able to separately clarify the effect of Ag content and growth temperature on large-sized (AgxCu1−x)2ZnSnS4 single crystals. In this study, centimeter-scale high-quality ACZTS single crystals were synthesized via an Ag-alloying strategy by a molten salt method for the first time. The results showed that the synthesized ACZTS have a high-quality single-crystal structure. A series of experiments was performed using various characterization techniques and it was found that Ag content and growth temperature were crucial in determining the size of ACZTS single crystals obtained through a molten salt method and that the associated CZTS base generated at high temperature was beneficial for further ACZTS single-crystal growth in this high-temperature environment. The experimental results showed that the growth mechanism of ACZTS crystals prepared using a molten salt method could be attributed to a type of epitaxial growth process. Our study provides a promising approach for growing large-sized ACZTS single crystals with high quality that can provide a potential single-crystal platform for the study of light-emitting diodes, photocatalytic hydrogen production, etc.
研究领域:
材料科学
·
光电材料
·
晶体生长
✓ 已验证
产品关联
DOI
高影响因子
Inorganic and Nano-Metal Chemistry
·
2019
·
IF 0.685
Xiuzhao Yin,Lingna Liu,Jihui Yang,Zifei Peng,Yuxiang Yang
Red nanofluorescent materials based on Y2O2S: Eu3+ were prepared by the molten salt method. Multiple small-sized Y2O2S sphere-shpaed particles ranging from 100 nm to 200 nm were prepared using different types of yttrium salts (Y(NO3)3·6H2O, YCl3, Y2(CO3)3·3H2O and Y2(C2O4)·6H2O). Based on a fluorescence performance test, their fluorescence properties reached up to 275 nm. We chose NaCl-Na2CO3 as the molten salt, and with all other experimental parameters being equal, the Y2O2S:Eu3+ particles produced were more uniform, with better diffraction properties and a smoother surface. With a molar ratio of 30 for molten salt and yttrium salt, more spherical Y2O2S:Eu3+ particles were produced small and sand homogeneous size. By using different dosage of molten salt, it was found that higher dosage of resulted in smaller particles with weaker fluorescence properties. Finally, by comparing the molten salt method with production by solid-state reaction, we found that the luminescence intensity of the product increased 20％compared to products obtained with the solid-state reaction.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Jiajiu Li,Rongxia Huang,Congfei Peng,Yejing Dai,Shunjin Xiong,Chunhui Cai,Hua-Tay Lin
In this study, plate-like Na 0.5 Bi 0.5 TiO 3 (BNT) templates with perovskite structure were obtained by two-step molten salt synthesis (MSS) method at a low temperature. Firstly, Bi 4 Ti 3 O 12 precursors were synthesized at 1030 °C in NaCl–KCl molten salt. Secondly, plate-like Na 0.5 Bi 0.5 TiO 3 particles with perovskite structure were obtained from plate-like layer-structured ferroelectric ceramic of Bi 4 Ti 3 O 12 by topochemical microcrystal conversion method. Result showed that excessive Na 2 CO 3 was beneficial to facilitate the low temperature synthesis. In the case of an excess of 30 mol% Na 2 CO 3 , plate-like BNT particles could be obtained by synthesis at temperatures ranging from 760 °C to 800 °C, which indicated a flexible processing route. Also, it has been observed that plate-like BNT particles show a high aspect ratio with 1 μm in thickness and 10–20 μm in length. These Na 0.5 Bi 0.5 TiO 3 plate-like particles can be good candidates for the preparation of lead-free BNT-based piezoelectric ceramics with oriented grain microstructure.
研究领域:
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）