Fundamental Research
·
2022
·
IF 0
Zhenghao Pu,Wei Wang,Zhe Wang,Mingyin Kou,Yiwa Luo,Jianbang Ge,Xin Tao,Mingyong Wang,Shuqiang Jiao
Despite its existence for more than 80 years, the titanium industry is still challenged by massive carbon emissions, high production costs, and large resource waste. More than one hundred million tons of Ti−bearing blast furnace slag (TB−slag) has been discarded in China because of the difficulty of reutilization, which requires efficient titanium extraction and recovery technologies. This paper describes a low−cost, carbon−emission−free method for Ti extraction and oxygen evolution via molten oxide electrolysis (MOE) vacuum distillation. After a comprehensive analysis of the binding energies and activities of liquid metals, the highlights of our study are as follows. 1) Sb has the best preferential deposition of Ti among a series of high−Ti−affinitive liquid metal cathodes (Cu, Ni, Pb, Sn, and Sb). 2) The Ir anode was first used in TB−slag with IrO 2 formed on its surface to protect it from further corrosion. 3) An alloy containing Ti and Ca can be obtained by MOE, and Ti and Ca metals can be refined by further vacuum distillation. 4) A closed loop is formed in the overall process owing to the recyclable Sb cathode and continuous feeding of TB−slag into the electrolyte. This simple, low−cost, and environmentally friendly method can realize the efficient utilization of Ti resources and achieve carbon neutrality.
研究领域:
材料科学
·
环境工程
·
冶金工程
✓ 已验证
DOI
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Shuiping Zhong,Tianhan Lei,Licong Liang,Xiaopeng Chi,Wei Weng,Chen Cheng,Ding Tang
Electrochemical fixation of CO 2 in molten salts as carbides for catalyzing the hydrogen evolution reaction can contribute to carbon neutrality and value-added conversion of CO 2 as well as facilitate the production of sustainable green hydrogen energy. However, the functional ability of the CO 2 -derived carbides still needs to be substantially improved. Herein, heterostructuring the CO 2 -derived Mo 2 C layer with MoP 2 is realized via electro-splitting of CO 2 in Ca 3 (PO 4 ) 2 -containing molten salt. The as-designed Mo 2 C–MoP 2 heterostructure layer presents significantly improved HER performances, namely overpotential being 109 mV @ 100 mA cm −2 and stability for 600 h @ 200 mA cm −2 , greatly outperforming both the bare Mo 2 C layer and commercial Pt candidates. The superior performances of the Mo 2 C–MoP 2 heterostructure are in one way attributed to the modified electronic structure that decrease the energy barrier of the Volmer rate-determining step for HER. In another way, the Mo 2 C–MoP 2 dual-phase increases the hydrophilicity ability of the catalytic layer, accelerating the detachment of the H 2 bubbles. The results can provide new insights for both value-added fixation of carbon dioxide and preparation of high-performance non-noble electrocatalyst.
研究领域:
材料科学
·
电化学
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2021
·Vol. 168
·期 11
·113505
·
IF 4.316
Yapeng Kong,Yu Xiao,Xuemin Liang,Yuran Chen,Liqiang Wang
The availability of casting Ni–Fe alloy as inert anode for direct electro-reduction of V2O3 in molten Na3AlF6-K3AlF6-AlF3 was investigated. The electrochemical oxidation behavior of anode as well as microstructural evolutions of formed oxide scale were systematically studied. The electrochemical characterization and reaction mechanism of the cathode oxide were also investigated to evaluate the influence of alloy anode on cathodic reduction process. The in situ formed three-layered oxide scale is compact and coherent, which is composed of an outermost Fe2O3 + FeAl2O4 skin layer, a Fe2O3 middle layer and a FeAl2O4 inner layer. The skin layer has a continuous, smooth structure and shows electrochemical activity. The Fe2O3 layer with a compact structure prevents inward diffusion of electrolyte and outward migration of metal cations. The innermost FeAl2O4 layer shows a loose structure and functions as a buffer layer to improve the peeling resistance of oxide scale. With the continuous extension of polarization time, the inner FeAl2O4 layer is slowly oxidized and becomes thinner, simultaneously, the dense Fe2O3 layer becomes thicker. Ultimately, metal vanadium product with fine rod-like particles can be obtained and the oxygen content in the metal vanadium is below 0.3 mass% within electrolyzing time of 2 h. The corresponding current efficiency is around 63%.
研究领域:
冶金学
·
材料科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
·
IF 5.774
Handong Jiao,Jianxun Song
Owing to the enhanced selective depolarization effect of the liquid Cu, Ti has been successfully collected from mixed oxide ores or slags by using advanced molten oxide electrolysis (MOE) configuring with a liquid Cu cathode. However, the products prepared via above process are Cu-Ti alloys. Additional process is needed for the separation of Ti from those alloys. To achieve this goal, here, we selected a simple electrochemical approach to separate Ti from the Cu-Ti alloys in molten salt. Compared to the pure Cu electrode, the Cu-Ti alloys with different Ti contents show more negative electro-oxidation potential, which, in principle, indicates that Ti could be electrochemically extracted from the Cu-Ti alloys. Furthermore, the results of constant current electrolysis show that the effective separation of Ti is affected by the anodic current density and the Ti content in the Cu-Ti alloys. Specifically, the anodic current density, enabling the effective separation of Ti, increases with the increase of the Ti content in the Cu-Ti alloys. We have fitted a relationship equation between the anodic current density and the Ti content, which will be helpful for guiding separation of Ti from the Cu-Ti alloys. These findings confirm the feasibility of the molten salt electrolysis for the separation of Ti, and also make the Ti extraction based on the advanced MOE a complete process.
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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2019
·
IF 4.084
Kaiyu Xie,Ali Reza Kamali
The low voltage electrochemical extraction of iron from iron oxide powder is reported. Hydrogen gas can be generated in molten LiCl at 660 °C by the electrochemical decomposition of steam at a voltage as low as only 0.97 V. Interestingly, individual submicrometer-sized iron oxide particles simply immersed in the melt can directly be reduced to semi-spherical metallic iron particles with a particle size of about 5 μm under the influence of hydrogen gas generated in-situ in the molten salt. The direct reduction of Fe 2 O 3 powder, instead of sintered Fe 2 O 3 pellets, which are commonly used as the cathode in the conventional molten salt electro-deoxidation processes, enhances the simplicity, energy consumption and the reaction kinetics of the molten salt hydrogen reduction process. In this method, the bottom surface of the graphite crucible acts as the cathode, resulting in a high rate of hydrogen cations discharge, hence a high current. The high temperature and low voltage characteristics of this method offer a scalable strategy for direct reduction of metal oxide particles in a green and low-cost way, where there is no requirement for the compaction of metal oxide powders into pellets. The mechanism involved in this hydrogen production and utilization methodology is discussed.
研究领域:
冶金学
·
电化学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2021
·
IF 4.641
Xuyang Bai,Dongxin Wang,Junyi Li,Shaolong Li,Yusi Che,Jilin He,Jianxun Song
This paper systematically studied the electrochemical behaviors of tantalum ions in NaCl-KCl molten salt, and pure metallic tantalum was collected on the cathode. Through a series of electrochemical methods such as cyclic voltammetry, square wave voltammetry, and chronopotentiometry, the reduction and diffusion processes of tantalum ions in NaCl-KCl molten salt were determined. The diffusion coefficient and nucleation mode of tantalum ions were investigated, and the electrodeposition was carried out at a certain potential. The results showed that the electrode reduction process of tantalum ion in NaCl-KCl molten salt at 1023 K is a two-step reaction Ta(V)→Ta(II)→Ta, and the reaction Ta(V)→Ta(II) was reversible and controlled by diffusion. The nucleation mode of tantalum ion was determined to be instantaneous nucleation by chronoamperometry. The cathode deposition product was analyzed by SEM, EDS and XRD, and it was confirmed that the deposition product was granular and the main component was tantalum.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Yang Xu,Handong Jiao,Mingyong Wang,Shuqiang Jiao
Vanadium-aluminum (V-Al) alloy, the master alloy for the well-known Ti-6Al-4V alloy, is mainly produced via aluminothermic reduction process of V 2 O 5 over the past decades. However, the reaction rate is too fast and it is difficult to control the product quality. Moreover, the utilization of aluminum is very low due to the production of Al 2 O 3 . In this work, a new method is proposed to prepare V-Al alloys by molten salt electrolysis of soluble NaVO 3 on a liquid aluminum (Al) cathode in molten NaCl-KCl melt. The results show that VO 3 − ions can be reduced to metallic V-Al alloys on the liquid Al cathode during electrolysis process. Furthermore, thermodynamic and electrochemical analysis indicate that the reduction of VO 3 − ions on the liquid Al cathode results from the combined effect of electroreduction and aluminothermic reduction. In this process, the liquid Al can not only reduce VO 3 − ions to V, but also to combine with vanadium to form V-Al alloys. However, unlike the traditional aluminothermic reduction process, alumina produced due to the aluminothermic reduction will be in-situ electro-reduced to aluminum, which will be helpful to increase the utilization of aluminum. As a result, when the electrolysis voltage is enough large, VO 3 − ions will be completely reduced. Al 3 V alloy without alumina can be obtained.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2022
·
IF 6.14
Zhuqing Zhao,Muya Cai,Haijia Zhao,Qiang Ma,Hongwei Xie,Pengfei Xing,Yan xin Zhuang,Huayi Yin
Electrolysis of SiO2 to produce Si in MgCl2-based molten salt faces the challenge of generating chlorine gas at a graphite anode. Herein, we replace the graphite anode with a Mg2Si alloy anode that is paired with a C–SiO2 cathode in molten NaCl–KCl–MgCl2. During the paired electrolysis, the Mg2Si anode releases two Mg2+ ions into the electrolyte, resulting in Si nanostructures, while the C–SiO2 cathode is reduced to C–Si composites without generating SiC. Thus, both electrode reactions obtain desired products, which eliminates chlorine gas evolution and tailors the structure and composition of Si. In addition, the electrolytic Si nanostructures and C–Si composites show enhanced lithium-storage performances. The anodic Si nanostructures display a high initial Coulombic efficiency of 82.7% and achieve a cycling capacity of 1490 mAh g–1 300 cycles later under 2 A g–1. The cathodic C–Si composite that remains inside the carbon matrix derived from rice husks maintains a stable capacity of 780 mAh g–1 and 92.1% capacity retention after 200 cycles at 0.5 A g–1. In addition to Si-based anode materials, this study offers an economical and green paired electrolysis approach to preparing various functional materials.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
·
2022
·Vol. 119
·期 31
·e2202884119
·
IF 12.779
Jiakang Qu,Xiang Chen,Hongwei Xie,Shuaibo Gao,Dihua Wang,Huayi Yin
Traditional sulfide metallurgy produces harmful sulfur dioxide and is energy intensive. To this end, we develop an anode electrolysis approach in molten salt by which sulfide is electrochemically split into sulfur gas at a graphite inert anode while releasing metal ions that diffuse toward and are deposited at the cathode. The anodic splitting dictates the “sulfide-to-metal ion and sulfur gas” conversion that makes the reaction recur continuously. Using this approach, Cu2S is converted to sulfur gas and Cu in molten LiCl-KCl at 500 °C with a current efficiency of 99% and energy consumption of 0.420 kWh/kg−Cu (only considering the electricity for electrolysis). Besides Cu2S, the anode electrolysis can extract Cu from Cu matte that is an intermediate product from the traditional sulfide smelting process. More broadly, Fe, Ni, Pb, and Sb are extracted from FeS, CuFeS2, NiS, PbS, and Sb2S3, providing a general electrochemical method for sulfide metallurgy.
研究领域:
冶金学
·
电化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2022
·
IF 4.598
Yong Cao,Chenguang Zhang,Chenyang Gao,Yong Xie,Chao Wang,Wei Lan,Fang Chang,Xu Zhang,Yu Zhao,Yanhua Cui,Yixiu Cui,Xiaojiang Liu
Composites consisted of ceramic paper, nanoparticles as well as molten salt electrolyte, are developed as the new electrolyte separators to substitute the traditional ones in thermal batteries, due to their flexible manufacture and good exhibition in electrochemical performance. However, the existed methods for fabricating the composites by roughly dip-coating with aqueous solutions, are suffering from drawbacks such as inefficiency, low consistence, or high temperature risk. Therefore, a new approach based on a melting-absorption-diffusion process, by using precursors without solvent, is developed. Firstly, the salts are accurately weighted. Then they melt on surfaces of ceramic papers and diffuse inside. After being treated at appropriate temperature for hours, high quality electrolyte separators based on ceramic papers are achieved. Compared to the traditional approaches, the new method can obviously increase and accurately control the amount of loaded nanoparticles and molten salts for each time. The achieved electrolyte separators also exhibit good electrochemical performance in single cells of thermal batteries compared with the traditional ones. With advantages like easy operation, high efficiency, and improved performance, this melting and in situ loading method holds broad prospect in preparing electrolyte separators at large scale.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Frontiers in Chemistry
·
2023
·
IF 5.5
Pang Zhongya,Tian Feng,Xiong Xiaolu,Li Jinjian,Zhang Xueqiang,Chen Shun,Wang Fei,Li Guangshi,Wang Shujuan,Yu Xing,Xu Qian,Lu Xionggang,Zou Xingli
The two-dimensional MAX phases with compositional diversity are promising functional materials for electrochemical energy storage. Herein, we report the facile preparation of the Cr2GeC MAX phase from oxides/C precursors by the molten salt electrolysis method at a moderate temperature of 700°C. The electrosynthesis mechanism has been systematically investigated, and the results show that the synthesis of the Cr2GeC MAX phase involves electro-separation and in situ alloying processes. The as-prepared Cr2GeC MAX phase with a typical layered structure shows the uniform morphology of nanoparticles. As a proof of concept, Cr2GeC nanoparticles are investigated as anode materials for lithium-ion batteries, which deliver a good capacity of 177.4 mAh g−1 at 0.2 C and excellent cycling performance. The lithium-storage mechanism of the Cr2GeC MAX phase has been discussed based on density functional theory (DFT) calculations. This study may provide important support and complement to the tailored electrosynthesis of MAX phases toward high-performance energy storage applications.
研究领域:
材料科学
·
能源存储
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 48
·期 3
·1233-1240
·
IF 3.3
Li Ding,Xin Kong,Yan Gong,Shanxin Yang,Yongde Yan,Yuan Deng,Yun Xue,Kai Zhu,Fuqiu Ma,Wei Liu
Bismuth (Bi) is a potential cathode material to drive the development of Gd extraction by molten salt electrolysis. However, study on the electrolytic reduction of Gd by Bi electrode in melts has not receive sufficient attention and understanding. Therefore, in this work, the electrochemical reactions, kinetic processes and thermodynamic properties in the electrolytic extraction of Gd were investigated by various electrochemical methods. The electrochemical results showed that only two Gd–Bi alloys were formed in the electrode reaction. Moreover, the exchange current density and activity coefficient during electrolysis were determined by galvanostatic pulse (GP) and Coulomb titration, respectively. The temperature dependence of both exchange current density and activity coefficient was further revealed. Finally, Gd was successfully extracted in the form of alloys through potentiostatic electrolysis.
研究领域:
冶金学
·
电化学
✓ 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）