JOURNAL OF MOLECULAR LIQUIDS
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2025
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IF 5.2
Peizhu Mao,Rongcen Zhao,Shaolong Li,Zepeng Lv,Jilin He,Jianxun Song
This work investigates the influence of fluoride ions on the electrochemical behavior and coordination properties of zirconium ions under different molar ratios of fluoride ions to zirconium ions, utilizing a combination of electrochemical and spectroscopic methods. The electrochemical properties of zirconium ions were examined at different fluoride ion contents within NaCl-KCl-ZrCl 4 and NaCl-KCl-K 2 ZrF 6 molten salt systems using cyclic voltammetry (CV), square wave voltammetry (SWV), and the chronopotentiometry (CP). Additionally, the samples underwent analysis through raman spectroscopy. The results demonstrate that zirconium ions reduction behavior is highly sensitive to fluoride ion content, which directly affects their reduction path, while the overall reduction trend remains consistent. Meanwhile, the coordination structure of zirconium ions with anions in molten salts has been modified. As fluoride ions are introduced, the Cl − ions present in the original ZrCl 6 2− complex are progressively replaced, giving rise to new coordination ions (ZrCl x F y n − ). When fluoride ions accumulate to a specific concentration, the formed coordination ions (ZrF x 2− ) have stronger stability to support them avoiding the formation of intermediate valence zirconium ions and be reduced to metallic zirconium via one step. Ultimately, electrodeposition experiments were conducted using fluoride ion and zirconium ion electrolytes at various molar ratios. The findings indicated that the current efficiency enhanced as the concentration of fluoride ions increased, and the volume of cathode deposits also rose with the addition of fluoride ions.
研究领域:
材料科学
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电化学
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
·
IF 22.1
Ao Zhang,Zhongqing Jiang,Shaoda Zhang,Penghua Lan,Naihua Miao,Weiheng Chen,Ning Huang,Xiaoning Tian,Yangjie Liu,Zhongyu Cai
We report the development of non-noble transition metal sulfide catalysts Mn-CuS-x for high-efficiency and selective H 2 O 2 production. In this study, we synthesized Mn-CuS-x with coral-shaped hierarchical porous structure through one-pot hydrothermal reaction. The Mn-CuS-x possesses large specific surface area with plenty of crystalline defects via heteroatom doping of Mn. The Mn-CuS-x kinetically favored 2e − pathway over 4e − pathway, resulting in high selectivity (>92%) to H 2 O 2 production and high H 2 O 2 concentration (∼24.5 mM at 0.6 V vs. RHE) within 3 h for the optimized Mn-CuS-2 catalysts (synthesized with a molar ratio of 1:3:8 (MnCl 2 ·4 H 2 O: CuCl 2 ·2 H 2 O: C 2 H 5 NS)). The Mn-CuS-2 showed excellent stability, indicating that the Mn-CuS electrocatalysts can simultaneously achieve both high stability and enhanced H 2 O 2 production. Our first-principles calculations further confirmed that the heteroatom Mn doping to CuS thermodynamically makes the 2e – -ORR pathway more favorable. This study provides a green, low-cost, and efficient route to produce H 2 O 2 , which is very promising for generating chemicals and liquid fuels.
研究领域:
材料科学
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电催化
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能源化学
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DOI
高影响因子
Advanced Energy Materials
·
2022
·Vol. 12
·期 34
·2201675
·
IF 29.698
Wenbo Liu,Xin Sui,Changkun Cai,He Huang,Rui Xu,Dongsheng Geng,Mingyang Chen,Jun Lu
Mg-CO 2 batteries, which exploit the greenhouse gas CO 2 as cathode active species, are an appealing next-generation battery candidate due to their high efficiency energy storage and value-added CO 2 utilization. However, compared with other metal-CO 2 systems, few aprotic Mg-CO 2 batteries have been reported so far as a result of several crucial problems including the comparatively slow redox reaction kinetics, a large decomposition energy barrier of the reduction products, and poor reversibility in their multi-electron three-phase cathodic reactions in nonaqueous environments. Herein, a rechargeable Mg-CO 2 battery is developed by using a Mo 2 C-CNTs catalytic cathode, a nonaqueous electrolyte, and a magnesium metal anode. The Mo 2 C-CNTs catalytic cathode can greatly reduce the charge overpotential of the Mg-CO 2 battery through tuning the CO 2 reduction pathways. The results of a variety of ex situ and in situ experiments as well as theoretical calculations show the Mo 2 C catalyst not only induces surface molecular adsorption for faster reaction kinetics but also improves the selectivity toward MgC 2 O 4 in the CO 2 reduction process for a higher Faraday efficiency. An exceptional low voltage hysteresis is achieved for the Mg-CO 2 battery. This work demonstrates a promising strategic option for rechargeable nonaqueous Mg-CO 2 batteries for simultaneously addressing energy and environmental issues.
研究领域:
能量存储
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电池技术
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材料科学
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电化学
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环境科学
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DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2022
·Vol. 33
·期 11
·103807
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IF 4.969
Jingxi Zhang,Yifan Niu,Yu Zhou,Shaohua Ju,Yongwan Gu
In this study, green tea was used as a reducing agent to prepare GT-nZVI/Cu nano-zero-valent iron-copper bimetallic materials for nitrate degradation. Through single factor experiments, the process conditions for nitrate removal by GT-nZVI/Cu were optimized. By measuring the contents of nitrate, nitrite, and ammonia nitrogen in the reaction products, the reduction pathway of nitrate-nitrogen in GT-nZVI/Cu was studied. In addition, the removal mechanism of nitrate by GT-nZVI/Cu was also analyzed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and kinetic experiments. The results showed that the size of GT-nZVI/Cu particles is between 50 and 70 nm, and they are irregular spherical shapes. The polyphenol antioxidants in green tea make GT-nZVI/Cu have stronger antioxidant properties, and the denitration products are mostly nitrogen. The addition of copper ions accelerates the reaction time and reaction rate. The maximum removal rate of nitrate by GT-nZVI/Cu within 75 min can be up to 99 %. After three repeated experiments, the removal rate of GT-nZVI/Cu can still reach 70 %. The removal mechanism of GT-nZVI/Cu has enhanced nitrate removal through complexation, redox, and adsorption co-precipitation. This study provides a new route for the green preparation and efficient application of nZVI.
研究领域:
环境化学
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纳米材料科学
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水处理技术
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环境功能材料
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污染控制化学
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应用催化
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DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2020
·Vol. 167
·期 8
·082501
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IF 3.721
Kejia Liu,Yaowu Wang,Yuezhong Di,Jianping Peng,Jing You,Naixiang Feng,Yi Zhang
Diagrams of the equilibrium potential E (relative to the standard chlorine electrode) against the activity of oxide ion ( expressed as its logarithm, pO2−) in systems of Ti-O-Cl-M (M=Li, Na, Mg, Ca, Sr and Ba) were plotted to investigate the electro-deoxidation of porous TiO2 pellets in different chloride molten salts, including LiCl, NaCl, MgCl2, CaCl2, SrCl2 and BaCl2. From the diagrams, the reduction pathways of TiO2 in different molten salts are similar; and the applied potential (vs Cl−/Cl2) on the cathode and O2− ion activity influence greatly on the reduction pathway of TiO2 and the deoxidation limit. To test and verify the results of the thermodynamic analysis, electro-deoxidation experiments in different molten salts were done to determine the actual pathways in the electrochemical reduction of TiO2 and the possible deoxidation limits in the molten salts. The results indicated that the thermodynamic analysis is helpful in predicting and understanding the electrochemical reduction process of titanium oxides though the experimental results differ slightly from the thermodynamic analysis in some systems. Low-oxygen Ti can be obtained only in molten CaCl2.
研究领域:
材料科学
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电化学
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冶金学
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DOI
高影响因子
Nature Catalysis
·
2022
·Vol. 6
·期 1
·6-15
·
IF 40.706
Kong Shuyi,Lv Ximeng,Wang Xin,Liu Zhengzheng,Li Zichuang,Jia Bingquan,Sun Du,Yang Chao,Liu Lijia,Guan Anxiang,Wang Jiacheng,Zheng Gengfeng,Huang Fuqiang
Methanol manufacturing by CO 2 electrolysis is a potential near-zero-emission route to carbon neutrality, but most of the previous studies in aqueous electrolytes have achieved poor methanol selectivity and yield. Inspired by hard–soft acid–base theory, we proposed that the CO 2 electroreduction pathways towards methanol or methane could be switched by tuning the electron delocalization state of Cu catalytic sites. On the basis of this hypothesis, we have designed and synthesized a cuprous cyanamide (Cu 2 NCN) crystal in which isolated Cu(I) ions strongly conjugated with NCN 2− exhibit highly delocalized electrons. Theoretical calculations showed that Cu 2 NCN substantially reduces the Cu–O interaction of the adsorbed *OCH 3 intermediate so that it is weaker than the O–C interaction at the critical reaction bifurcation point of Cu‒*O‒CH 3 , thus switching the pathway to release *OCH 3 and form methanol. The Cu 2 NCN catalyst exhibits one of the highest recorded CO 2 -to-CH 3 OH selectivities (70%) and an outstanding partial current density of −92.3 mA cm −2 in aqueous electrolyte, corresponding to a CH 3 OH electroproduction rate of 0.160 μmol s −1 cm −2 .
研究领域:
电化学
·
材料科学
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环境化学
·
催化
✓ 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）