CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Yuan-Pei Lan,Chaoyi Chen,Junqi Li,Xuewen Xia,Xisong Mao,Hao Zhou
Homogeneously Eu 3+ doped LaOCl single crystals are firstly synthesized in a molten KCl-LiCl flux, and the well-shaped LaOCl:Eu 3+ polyhedral micro-plates exhibit noticeable luminescent properties. The bulk LaOCl:Eu 3+ micro-plate with a width of 1.03 μm and 1.37 μm in length shows a single crystal characteristic with the crystal face orientation of [00 1 ‾ ]. Both XRD patterns and EDS mapping indicate that the Eu 3+ ions have been homogeneously doped into LaOCl lattice. LaOCl:Eu 3+ nucleuses generated in molten KCl-LiCl flux at even 350 °C benefited to the decomposition of La(OH) 3 :Eu 3+ precursor, and polyhedral LaOCl micro-plate is easily formed in molten KCl-LiCl salt due to the solid-ionic reaction and crystal growth. The luminescent properties of LaOCl:Eu 3+ are firstly enhanced and then weakened with the increasing concentration of the doped Eu 3+ , 6% Eu 3+ doped LaOCl:Eu 3+ exhibits the best luminescent properties which can be used as a potential LED material.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
WATER RESEARCH
·
2024
·
IF 11.4
Peng Feng,Donghai Xu,Youwei Zhi,Bing He,Shuzhong Wang,Yaling He,Yang Guo
This work aims to explore the ability of molten salt to solve salt deposition in supercritical water (SCW) related technologies including supercritical water oxidation and supercritical water gasification, with KNO 3 and Na 2 SO 4 as examples. In the pure KNO 3 solution, the two-phase layering of high-density KNO 3 molten salt (settling at the reactor bottom) and low-density saturated KNO 3 -SCW salt solution (flowing out at the top outlet of the reactor) was formed in a kettle-reactor with about 6.5 ratio of depth to inner diameter, thereby improving the accuracy of measured solubilities. The precipitation macro-characteristics of mixed KNO 3 and Na 2 SO 4 in SCW were investigated under different feed concentration conditions. The results showed that Na 2 SO 4 deposition on the reactor sidewall could be reduced by more than 90 % when the mass ratio of KNO 3 to Na 2 SO 4 in the feed was only 0.167. No visible salt deposition was observed on the sidewall when the ratio was 0.374. All solid deposited salts were converted into the liquid molten salt as the ratio reached 3.341, and thus could easily flow out of the reactor, without plugging. ‘Molten salt dissolution’ mechanism may provide a more plausible explanation for mixed KNO 3 and Na 2 SO 4 in SCW. In addition, the precipitation micro-mechanisms of mixed KNO 3 and Na 2 SO 4 , and the critical conditions of avoiding sidewall deposition and reactor plugging were proposed. This work is valuable for overcoming the salt deposition problem in SCW-related technologies.
研究领域:
化学工程
·
环境科学
·
超临界流体技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2019
·
IF 2.781
Jun Wei Wang,Zelong Bao,Rong Qiao Xiang,Gao Hao Hu,Yong Kang Hu,Qing Ma,Bin Li,Hong Guang Jia
As a solar energy storage medium or heat transfer medium at moderate-high temperature, the molten NaCl-MgCl 2 has the advantages of high stability and low cost. But a pipe and container material with Cr will be corroded badly in a molten chloride. Based on the founded corrosion resistance phase (Fe 0.64 Ni 0.36 ) in previous experiments, the corrosion behavior of a new alloy of Fe-37 wt% Ni with rare earth alloy element Sc in the molten eutectic NaCl-MgCl 2 at 520 °C was studied. The corrosion rate of the Fe-37 wt% Ni alloy is lower than that of the researched Fe-based superalloys (GH1035 and GH1140). After corrosion for 15 h, a porous structure with Ni-rich and Fe-depletion is formed at the local location on the Fe-37 wt% Ni surface. For the specimens with Sc (0.3 and 0.5 wt %), a compact protective MgO layer covers on the porous structure, which prevents further corrosion in the molten salt . It is speculated that the Sc is oxidized to Sc 2 O 3 directly or by the chlorination-oxidation reactions, which improves the adhesion strength between the MgO layer and the alloy matrix by the effects of inhomogeneous nucleation and pinning.
研究领域:
材料科学
·
腐蚀工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2021
·
IF 3.383
Jinzhao Guan,Kaiyu Xie,Aimin Liu,Zhongning Shi,Gong Chen,Miroslav Boca
In this study, Al–Si alloy, a precursor of the solar-grade silicon , was prepared via the aluminothermic reduction–molten salt electrolysis of SiO 2 in KF–AlF 3 molten salt by employing liquid aluminum as the working cathode. The reaction mechanism of the aluminothermic reduction of SiO 2 in KF–AlF 3 molten salt at 750 °C was determined by thermogravimetry–differential scanning calorimetry. The reaction rate equation for the aluminothermic reduction of SiO 2 in KF–AlF 3 molten salt was: d α dt = 7.156 × 10 24 e − 4.688 × 10 5 RT ( 1 − α ) 1.734 . In 49.4 wt% KF–47.6 wt% AlF 3 –3 wt% SiO 2 molten salt at 750 °C, the Si content in the Al–Si alloy obtained by the aluminothermic reduction–molten salt electrolysis of SiO 2 was 24.53 wt%. Compared with solely aluminothermic reduction of SiO 2 , the current efficiency in the process of the aluminothermic reduction–molten salt electrolysis of SiO 2 was evaluated. The results reveal that the Al–Si alloy is predominantly prepared in the aluminothermic reduction step, while supplemented by electrolysis. The calculated Faradic current efficiency of the proposed aluminothermic reduction–molten salt electrolysis process was 28.4%.
研究领域:
材料科学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
X.J. Xue,J. Dong,C.Y. Zhao
Molten carbonate salt is one of the promising candidates for high-temperature thermal energy storage tailored towards advanced pumped-thermal energy storage and next generation concentrated solar power technologies. However, severe corrosion of structural materials exposed to molten carbonate salts poses one of the most pivotal threats in terms of limiting their large-scale application at ever-escalating temperatures. Here, we elaborate the compatibility of three commercial austenitic stainless steels specifically SS310, SS316L and Incoloy 625 with Li 2 CO 3 -K 2 CO 3 (28–72 wt%) eutectic salt. The corrosion behavior and corrosion mechanism of Fe-Cr (SS316L), Fe-Cr-Ni (SS310) and nickel-based (In625) alloys at 600 °C in air were also investigated. It revealed that SS310 exhibited better corrosion resistance compared to SS316 and In625, with weight loss of 23.8 mg/cm 2 and corrosion rate of 522 μm/year after 500 h of exposure at 600 °C. This implies that higher Ni content of the alloy may not necessarily improve the corrosion resistance, it is associated with the basicity of the molten and the solubility of Ni salt in the melt. ICP analysis indicated that the salts exposed to SS310 and In625 at the same exposure time both had nearly 11 times more Ni than that exposed to SS316. Precisely, it is related to the behavior of the Cr-enriched zones formed in the corrosion layers of different alloys. The corrosion mechanism of SS310 specimens in molten carbonate can be generally divided into the following steps: (i) selective oxidation of the metal elements and lithiation reactions of the metal oxides to generate a passivation scale, (ii) an ever-growing middle transition scale consisted of mixed metal oxides and lithium-containing compounds, (iii) cracking and peeling off of the corrosion scale.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Yadong Jia,Zhaohaitan Zhu,Jianbang Ge,Lei Dai,Mingyong Wang
Stable inert anode presents a promising alternative to active graphite anodes in molten salt electrolysis, offering a significant reduction in CO 2 emissions. However, developing such anodes remains a significant challenge. In this study, a novel metal-spinel cermet inert anode for use in CaCl 2 -based molten salts was introduced. Three spinel materials—NiFe 2 O 4 , MgFe 2 O 4 , and MgAl 2 O 4 —were synthesized and their electrochemical properties were compared. It was observed that NiFe 2 O 4 emerged as the most effective spinel ceramic. Subsequently, 20 wt%(50Cu-Ni)- x NiO-NiFe 2 O 4 ( x = 0, 10, 20) were prepared and evaluated. Furthermore, according to polarization behavior, density, and conductivity, the 20 wt%(50Cu-Ni)-10NiO-NiFe 2 O 4 anode exhibited superior performance in CaCl 2 -CaO molten salt, which outperformed conventional SnO 2 inert anodes. Its corrosion rate was measured at only 1.25 × 10 −3 g cm −2 h −1 over 20 h of electrolysis. Additionally, carbon spheres were successfully prepared using the 20 wt%(50Cu-Ni)-10NiO-NiFe 2 O 4 cermet anode in CaCl 2 -5 wt% CaCO 3 molten salt, thereby achieving a current efficiency of ∼85.5 %. The NiFe 2 O 4 -based cermet exhibited significant potential as an inert anode for sustainable metallurgical processes.
研究领域:
冶金学
·
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Xiao-Hui Yang,Guo-Hua Zhang
In this study, ultrafine borides powders including (W,Mo)B, (W,Mo)B 2.5 and (Mo,W)AlB were successfully fabricated via boronizing ultrafine W-Mo solid solution composite powder with B 4 C as the boron source under the assistance of Ca melt or Al melt. Ultrafine W-Mo solid solution powder was obtained by using a two-stage reduction route to reduce the precursor powder synthesized by spray drying. Meanwhile, the effects of Mo/W ratio on the phase composition, morphological characteristics and particle size distribution of boride solid solution composite powder were thoroughly investigated. The shift of diffraction peak in the XRD spectrum, the linear change of lattice constant and the homogeneous distributions of W, Mo, B and Al in the EDS energy spectrum comprehensively confirmed that the boride solid solution with different Mo/W ratios could be prepared. Due to the essentially insolubilities of W and Mo in Ca melt, the (W, Mo)B grains grew following a template growth mechanism, and inherited the nearly spherical morphology feature of ultrafine W-Mo solid solution composite powder with a particle size of approximately 200 nm. Nonetheless, as a result of the high solubilities of W, Mo, and B in Al melt, the process of dissolution-precipitation led to the formations of flaky (W, Mo)B 2.5 and short rod-shaped (Mo, W)AlB.
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
JOURNAL OF NUCLEAR MATERIALS
·
2020
·
IF 2.485
Yi-Chuan Liu,Ya-Lan Liu,Yuan Zhao,Zhe Liu,Tong Zhou,Qing Zou,Xian Zeng,Yu-Ke Zhong,Mei Li,Zhong-xuan Sun,Wei-Qun Shi
For UO 2 -based spent fuel , it is usually electrochemically reduced and then refined in molten salt with respect to the so-called pyrochemical reprocessing approach. In this work, we report a new method with the assistance of NH 4 Cl to directly achieve convenient separation of UO 2 over La 2 O 3 in Ar atmosphere which does not require an electrochemical process . According to the results from both powder and pellet samples, the separation is achieved by dissolving La 2 O 3 into the LiCl–KCl molten salt with NH 4 Cl, whilst UO 2 cannot be dissolved and remains in solid form. It was found that the dissolution kinetics of La 2 O 3 in the powder sample was fast and its removal efficiency in the mixture of La 2 O 3 and UO 2 was high, but a specific amount of UO 2 was also dissolved, which lead to a low recovery efficiency of UO 2 . In contrast, when the pellet samples after sintering at 1473 K were used, the recovery efficiency of UO 2 can be increased. Nevertheless, the dissolution kinetics of La 2 O 3 was correspondingly reduced, and more NH 4 Cl was required to complete the dissolution reaction . By improving and optimizing the experimental conditions, the UO 2 recovery efficiency of 92.0% can be achieved, while the removal efficiency of La 2 O 3 was 94.4%. More importantly, this novel separation method may be also useful for the separation of UO 2 over mixed lanthanide oxides.
研究领域:
核化学与化工
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2023
·Vol. 13
·期 5
·878
·
IF 3.9
Yue Huang,Renhao Si,Yi Wei
Lignin is a crucial raw material for the synthesis of phenol due to its high oxygen concentration; however, the selectivity of phenol in pyrolysis products is low. This study chose cerium oxide as the coupling agent for molten salts, and the reaction’s process conditions—including temperature and catalyst dosage—were examined. The influence of metal loading on the reaction and byproducts of catalytic pyrolysis was examined. The outcomes demonstrated that the best monophenol production was accomplished at 550 °C and an Fe loading of 15 wt.%, with 93.93 wt.% monophenols in the bio-oil. While methoxy was more easily broken and rearranged, producing more monophenols, the presence of the catalyst enhanced the oxidation of Cα-OH and the breaking of β-O-4 bonds, which is significant for the study of lignin pyrolysis.Keywords:molten carbonates;pyrolysis;deoxidation;monophenols;lignin
研究领域:
化学工程
·
生物质能研究
✓ 已验证
产品关联
DOI
高影响因子
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
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2025
·Vol. 172
·期 1
·012505
·
IF 3.3
Shangrun Ma,Fuxing Zhu,Lingxin Kong,Liguo Zhu
Titanium and its alloys are widely used in aerospace and ocean engineering because of their excellent properties. Molten salt electrolysis is a cost-effective and efficient method for producing titanium powder. However, titanium powder prepared via this method contains high oxygen levels. To address this issue, a novel approach for producing low-oxygen titanium powder by molten salt electrolysis containing LaCl3 is proposed in this study. Molten salts were selected and their physicochemical properties determined. The density, viscosity, and surface tension of the molten salt increased with LaCl3 content and decreased with increase in temperature in the NaCl-KCl-MgCl2-LaCl3-TiClx molten salt system. For optimal separation of electrolytic products from the molten salt and electrolytic slag, lower LaCl3 content and higher temperatures are recommended. Electrochemical tests revealed that the Ti precipitation reaction was quasi-reversible and diffusion-controlled. Finally, molten salt electrolysis experiments were conducted, showing that the oxygen content of the titanium powder decreased with increased temperature, LaCl3 concentration, and electrolysis time. At 4 wt% LaCl3, titanium powder with a low oxygen content of 500 mass ppm oxygen was obtained by electrolysis at 850 °C and 2.5 V for 1 h. This study provides theoretical guidance for the low-cost, short-process preparation of low-oxygen titanium powder.
研究领域:
材料科学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2025
·Vol. 172
·期 3
·032506
·
IF 3.3
Wenqiang Li,Aimin Liu,Yanying Jiang,Chengdan He,Fengguo Liu,Yongjun Wang,Xianwei Hu,Jin Wang,Zhongning Shi
Silicate minerals on S-type asteroids are a potential resource for in situ production of silicon. We investigated the feasibility of synthesizing silicon from Mg2Si3O8 through electrolysis in NaF-LiF molten salt. Solubility of Mg2Si3O8 in NaF-LiF molten salt was determined using isothermal saturation. Dissolution equilibrium is reached after 120 min, and the solubility of Mg2Si3O8 in NaF-LiF molten salt at 750 °C is 28.9%. Electrochemical studies revealed that the reduction of Si(IV) in NaF-LiF molten salt is a two-step process. Si(IV) was reduced to Si(II) at −1.1 V (vs Pt), and Si(II) was further reduced to metallic silicon at −1.2 V (vs Pt). Electrolysis of Mg2Si3O8 in NaF-LiF molten salt was conducted at 750 °C using a high-purity graphite sheet as anode and a silver sheet as cathode. Electrolysis products were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). XRD indicated that the main phase of the electrolysis products was silicon when cell voltages were 2.0, 2.5, 3.0, and 3.5 V. Raman spectroscopy confirmed the presence of crystal silicon. SEM and EDS revealed that the electrolysis products exhibit granular morphology, and silicon concentration reached a maximum value of 98.14% when the cell voltage was 2.5 V.
研究领域:
材料科学
·
天体资源开发
✓ 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）