ANALYTICAL CHEMISTRY
·
2025
·
IF 6.7
Chenlu Lin,Xiao Yang
Molten CaCl2 is a viable solvent and electrolyte for extracting target elements from their oxides through electrolysis. However, the accumulation of O2– during electrolysis presents a significant challenge for the commercial application of CaCl2-based technologies. Understanding the behavior of O2– in the melt is crucial for optimizing the process. To address this, we developed an electromotive force (EMF) measuring system to monitor O2– behavior during the Si electrodeposition in molten CaCl2. We explored the thermodynamic properties of O2– in molten CaCl2–CaO (XO2– < 0.03) at 1123 K. The relationship between activity and molar fraction of O2– was established as aO2– = XO2–2.2, indicating strong interactions between O2– and other ions in the melt. EMF measurements confirmed the accumulation of O2– during the electrolysis in molten CaCl2–CaO–SiO2, as evidenced by the significant increase in aO2–. Notably, this accumulation becomes more pronounced with larger cathode areas, which leads to greater carbon contamination. Further investigation revealed that solid SiO2 effectively reduces aO2– in molten CaCl2–CaO to lower levels. By immersing solid SiO2 in melt during electrolysis, the accumulation rate of O2– is slowed, thereby inhibiting carbon contamination and improving current efficiency. These findings provide valuable insights into the use of the EMF measuring system as an effective tool for revealing O2– behavior and optimizing electrolysis processes in molten CaCl2.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2021
·Vol. 13
·期 28
·12157-12163
·
IF 7.79
Kaixiang Shen,Qiang Wei,Xin Wang,Qiang Ru,Xianhua Hou,Guannan Wang,Kwan San Hui,Jiadong Shen,Kwun Nam Hui,Fuming Chen
Multifunctional electrocatalytic desalination is a promising method to increase the production of additional valuable chemicals during the desalination process. In this work, a multifunctional desalination device was demonstrated to effectively desalinate brackish water (15 000 ppm) to 9 ppm while generating formate from captured CO2 at the Bi nanoparticle cathode and releasing oxygen at the Ir/C anode. The salt feed channel is sandwiched between two electrode chambers and separated by ion-exchange membranes. The electrocatalytic process accelerates the transportation of sodium ions and chloride ions in the brine to the cathode and anode chamber, respectively. The fastest salt removal rate to date was obtained, reaching up to 228.41 μg cm−2 min−1 with a removal efficiency of 99.94%. The influences of applied potential and the concentrations of salt feed and electrolyte were investigated in detail. The current research provides a new route towards an electrochemical desalination system.
研究领域:
环境科学
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电化学工程
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Reaction Kinetics Mechanisms and Catalysis
·
2024
·
IF 1.7
Yan Jiaqi,Fu Weiwen,You Kuiyi,Zhao Fangfang,Luo He’an
A solvent-free, acid-free, and efficient strategy was developed for the selective preparation of 4-nitro-o-xylene (4-NOX) from the catalytic nitration of o-xylene with NO 2 mediated O 2 over BiCl 3 immobilized silicic acid catalyst (BiCl 3 -SA). The results indicated that the Lewis acid BiCl 3 -SA conjoined NO 2 –O 2 as a composite system synergistically promotes o-xylene conversion and 4-NOX selectivity. Under optimal conditions, 52.4% of o-xylene conversion with 68.4% 4-NOX selectivity was obtained at 35 °C. The characterization demonstrated that the highly dispersed metal Bi species form stable chemical bonds with the SA surface, which can effectively inhibit the loss of metal species and generate abundant acid sites. The developed catalyst is not only inexpensive but also has excellent stability and catalytic performance. Furthermore, a plausible mechanism for the catalytic nitration of o-xylene using NO 2 as a nitration agent over BiCl 3 -SA was proposed. This work provides an eco-friendly and practical protocol for improving desirable 4-NOX selectivity and reducing the discharge of acidic wastewater, with potential application prospects. Graphical abstract
研究领域:
催化化学
·
环境科学
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产品关联
DOI
高影响因子
ACS Omega
·
2019
·
IF 2.584
Wenting Si,Bin Yang,Qingni Yu,Lecheng Lei,Jingke Zhu
CO2 emission is generally regarded as the major contributor to global climate change, and polyethylenimine (PEI)-based CO2 adsorbents are promising materials for the capture of low concentration CO2. This paper deals with the deactivation kinetics of PEI-based CO2 adsorbents used for the capture of low concentration CO2. EA and TG analyses demonstrated that thermal degradation and O2-induced deactivation of the adsorbents occurred simultaneously under air exposure conditions. It was found by N2 exposure experiments at the temperature of 50–80 °C that the thermal degradation of PEI-based adsorbents followed a first-order reaction model with an activation energy of 80.98 kJ/mol and a pre-exponential factor of 6.055 × 108 (h–1). The parallel reaction model was employed to distinguish the O2-induced deactivation from the thermal degradation of the adsorbents through air exposure experiments within 50–80 °C. The O2-induced deactivation exhibited a second-order reaction with an activation energy of 74.47 kJ/mol and a pre-exponential factor of 6.321 × 106 (%–1·h–1). The results of simulating the overall deactivation of the adsorbents by the parallel reaction kinetic model were well consistent with those of the experiments, proving that the parallel reaction model was feasible for the description of the deactivation of PEI-based adsorbents.
研究领域:
环境科学
·
材料化学
✓ 已验证
DOI
PubMed
高影响因子
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
·
2025
·Vol. 65
·期 2
·e20062
·
IF 16.9
Yicheng Zeng,Yin Zhou,Fangze Liu,Hongbo Li
Understanding electrocatalyst-intermediate orbital interaction in oxygen evolution reactions (OER) is critical for designing high-performance lithium–oxygen (Li–O 2 ) batteries, yet remains a significant challenge. In this study, we employed a CdSe-based catalyst as a model cathode to deeply investigate the catalyst–intermediate interaction and its effect on OER activity. Compared to the 4d orbital electronic states of Cd in CdSe, electron transfer from CdSe to ZnS in the CdSe/ZnS heterojunction results in a downward shift of the Cd 4d suborbital energy levels. The differences in the Cd 4d orbital electronic states between CdSe and CdSe/ZnS cause distinct orbital interaction mode with LiO 2 intermediate, ultimately leading to variations in OER activity. Specifically, compared to the strong Cd 4d xy –O 2P x/y orbital interaction mode between CdSe and LiO 2 , the weaker Cd 4d z 2 –O 2P y orbital interaction mode between CdSe/ZnS and LiO 2 significantly reduces the activation energy of the rate-determining step, thereby enhancing OER activity. This finding provides theoretical guidance for the design of OER electrocatalysts in Li–O 2 batteries. Graphical We demonstrate that the OER performance of Li–O 2 batteries primarily depends on the orbital interaction mode between the catalyst and the intermediates. In contrast to the strong Cd 4d xy –O 2P x/y orbital interaction mode between CdSe and LiO 2 , the weaker Cd 4d z 2 –O 2P y orbital interaction mode between CdSe/ZnS and LiO 2 significantly reduces the charge activation energy barrier, thereby enhancing OER catalytic activity.
研究领域:
电化学
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材料科学
·
储能
·
催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Jinyin Cheng,Haochang Zhang,Zhixin Wang,Yaqing Zhou,Kangzhe Yu,Yan Cheng,Zhaozhe Yu,Xiao Huang,Bingbing Tian
Emerging halide superionic conductors with remarkable oxidative stability and deformability , making them a potential game-changer for high-performance all-solid-state Li batteries (ASSLBs). The recently reported Li 2 ZrCl 6 (LZC) with low cost possess great potential. However, its ionic conductivity at 25 °C is below 1 mS cm −1 . Herein, we developed a Li-richened strategy to LZC by doping O 2− at Cl − site via a mechanochemical method to form oxychloride electrolytes Li 2+ x ZrCl 6− x O x (0 ≤ x ≤ 1.8), resulting in high ionic conductivity up to 1.46 mS cm −1 at room temperature (RT). The experimental results and theoretical calculations (ab initio molecular dynamics simulations) demonstrate that the Li 2 O doping leading to a Li-richened LZC lattice effectively enhances the Li + conductivity in solid-state electrolytes (SSEs). Significantly, an increasing O 2− substitution in the Li 2+ x ZrCl 6− x O x microcrystalline framework induces a progressive structural evolution from triangular to monoclinic phases, accompanied by a redistribution of Li + . Furthermore, the ASSLBs formed by Li 3.4 ZrCl 4.6 O 1.4 (LZCO) with Li-In anode and bare LiCoO 2 cathode shows excellent long-term cycling stability (94 % capacity retention for 600 cycles at 1 C) and high-rate performance (105.7 mAh g −1 at 2 C). This exploratory study provides a promising strategy to facilitate the application of low-cost LZC-based SSEs for high-performance ASSLBs.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
·
2025
·
IF 3.1
Lin Chenlu,Yang Xiao
Molten CaCl 2 is increasingly recognized for its potential in developing innovative mineral and material processing technologies as an effective solvent and electrolyte. However, controlling the accumulation of free O 2− remains a major challenge. This work explores the feasibility of eliminating free O 2− in molten CaCl 2 by adding MgCl 2 . Thermodynamic analysis suggests that the introduction of Mg 2+ favors the precipitation of O 2− as insoluble MgO (Mg 2+ + O 2− → MgO↓). Experimental results confirm a rapid and vigorous reaction producing sub-micron MgO particles, which initially suspend, then coalesce, and eventually settle at the bottom. The process’s efficiency depends on the dosage of MgCl 2 added. A sub-stoichiometric dosage inadequately removes O 2− , while a hyper-stoichiometric dosage disrupts the melt stability due to the widespread dispersion of soluble Mg(II) and MgO particles. A near-stoichiometric dosage, on the other hand, leads to optimal performance by facilitating the formation of Mg 2 O 2+ , enabling localized MgO precipitation and thus preventing contamination of the bulk melt. These findings provide a foundation for designing more efficient and environmentally friendly molten CaCl 2 -based processes for industrial applications.
研究领域:
材料科学
·
冶金学
·
无机化学
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高温化学
·
过程工程
✓ 已验证
产品关联
DOI
高影响因子
IONICS
·
2018
·Vol. 25
·期 4
·1669-1677
·
IF 2.347
Yuan Jiashu,Liu Zhihao,Wen Yandi,Hu Huili,Zhu Yongming,Thangadurai Venkataraman
Li–oxygen battery provides much higher specific energy density compared to conventional Li–ion batteries, but there is a lack of desired cathodes which show lower over-potential during the charging cycle. Here, we report the effect of surface morphology of carbon-free spinel-like NiCo 2 O 4 nanowires and nanosheets on Ni foam on cathode performance in Li–O 2 battery. Two hierarchical structured NiCo 2 O 4 cathodes were synthesized by using a hydrothermal method. Physical, chemical, and electrochemical properties of NiCo 2 O 4 were characterized using powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, BET surface area, electrochemical AC impedance spectroscopy, and linear sweep voltammetry. Scale-like NiCo 2 O 4 electrode showed the highest specific capacity, compared to that of rod-like morphology, which seems due to a superior catalytic activity for oxygen reduction reaction, with lower charging over-potential, high discharge capacity, and excellent cycle performance.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2023
·
IF 11.4
Yanfeng Wang,Peiyun Wei,Zihan Shen,Chao Wang,Jie Ding,Wenkai Zhang,Xin Jin,Chad D. Vecitis,Guandao Gao
Hydrogen peroxide (H2O2), as a critical green chemical, has received immense attention in energy and environmental fields. The ability to produce H2O2 in earth-abundant water without relying on low solubility oxygen would be a sustainable and potentially economic process, applicable even to anaerobic microenvironments, such as groundwater treatment. However, the direct water to H2O2 process is currently hindered by low selectivity and low production rates. Herein, we report that poly(tetrafluoroethylene) (PTFE), a commonly used inert polymer, can act as an efficient triboelectric catalyst for H2O2 generation. For example, a high H2O2 production rate of 24.8 mmol gcat–1 h–1 at a dosage of 0.01 g/L PTFE was achieved under the condition of pure water, ambient atmosphere, and no sacrificial agents, which exceeds the performance of state-of-the-art aqueous H2O2 powder catalysts. Electron spin resonance and isotope experiments provide strong evidence that water–PTFE tribocatalysis can directly oxidize water to produce H2O2 under both anaerobic and aerobic conditions, albeit with different synthetic pathways. This study demonstrates a potential strategy for green and effective tribocatalytic H2O2 production that may be particularly useful toward environmental applications.
研究领域:
化学
·
环境科学
·
能源
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PROCEEDINGS OF THE COMBUSTION INSTITUTE
·
2022
·Vol. 39
·期 1
·315-324
·
IF 6.535
Qianjin Lin,Wanxiong Liao,Jia Cheng,Chun Zou,Bin Yang,Wenxiang Xia
Few studies on the low-temperature combustion behavior of MIPK, being a promising fuel additive , have been conducted. In this work, ignition delay times (IDTs) of MIPK were measured in the temperatures ranging between 780–910 K and pressures of 20 and 25 bar using a rapid compression machine (RCM). Oxy-fuel combustion combined with biofuel could remove CO 2 from the atmosphere. The IDTs of MIPK were measured in the temperatures ranging between 1125–1600 K under the O 2 /CO 2 atmosphere at the pressures of 1 and 10 bar using a shock tube . A low to high-temperature MIPK kinetic model (HUST-MIPK model) was proposed, in which the low-temperature sub-model consists of 19 low-temperature reaction classes and was constructed by analogy-based method, the high-temperature sub-model was adapted from the works of Cheng et al.. The predictions of HUST-MIPK model are in good agreement with the present low-temperature IDTs, high-temperature O 2 /CO 2 atmosphere IDTs, and the literature experimental data. The negative temperature coefficient (NTC) behavior was not observed in the temperature range from 790 to 910 K in the present RCM experiments, but was observed for methyl propyl ketone (MPK) and diethyl ketone (DEK) under similar conditions. The low-temperature chemistry of three pentanone isomers (MIPK, MPK, and DEK) was compared using the flux and sensitivity analysis. The comparison of the experimental high-temperature IDTs between O 2 /CO 2 and O 2 /Ar atmospheres indicates the IDTs of MIPK under O 2 /CO 2 atmosphere are longer than those under O 2 /Ar atmosphere at 1 bar, and the effects of CO 2 are almost independent of the pressure. The physical and chemical effects of CO 2 on the ignition were studied in detail.
研究领域:
燃烧化学
·
燃料化学
·
反应动力学
·
能源工程
·
大气环境影响
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Yeshuang Wang,Mingxian Duan,Zhelin Su,Chao Yang,Bingning Wang,Jiawei Kou,Huiling Fan
The abundant Fe 3+ Lewis acidic sites and well-developed pore structure endow the Fe-MOFs with great potential for H 2 S catalytic oxidation at room temperature, but their performance is inferior owing to the insufficient redox ability of the Fe 3+ species inherent in frameworks. Herein, an effective protocol was proposed for the first time to remarkably improve the catalytic oxidation performance of MIL-100(Fe) under ambient conditions through the introduction of Fe 2+ coordinatively unsaturated site (CUS) species into the framework. As expected, the sample after modification had a superior H 2 S breakthrough capacity of 267.3 mg S/g, an 18.4-fold increase compared with that without Fe 2+ CUS (14.5 mg S/g). The introduced Fe 2+ species triggered the Fe 3+ /Fe 2+ redox cycle for H 2 S catalytic oxidation by enhancing the oxidative ability of the Fe 3+ CUS intrinsic to the framework. Moreover, the Fe 2+ CUS was also found act as an active site for O 2 activation into O 2 ∙– , which not only provides an additional pathway for H 2 S catalytic oxidation but also accelerates the redox cycling of Fe 3+ /Fe 2+ during the catalytic oxidation process. On the basis of the experimental findings, a plausible catalytic mechanism involving mixed-valence iron sites in MIL-100(Fe) was proposed.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2022
·Vol. 189
·期 12
·1-10
·
IF 6.408
Sun Zhuo,Lu Juan,Zhang Xin,Shan Xiangyu,Wu Qian,Li Chao,Li Huiling,Yang Shuning,Tian Li
Electrospun nanofibers containing CdTe@ZnNi-metal–organic frameworks (CdTe@ZnNi-MOF NFs) were used for the first time in luminol-O 2 electrochemiluminescence (ECL) system to construct ECL sensor for chlorpyrifos (CPF) detection. Firstly, CdTe@ZnNi-MOF NFs obtained by blending method was used to modify the surface of a glassy carbon electrode, and then, the proposed solid-state ECL sensor was constructed by dropping luminol onto the surface of nanofiber benefiting from chitosan (CTS) viscosity. CdTe@ZnNi-MOF NFs with its large surface area and porosity can be used not only as luminol carrier but also as co-reaction promoter of the ECL system. The ECL sensor obtained satisfactory results in weakly alkaline solution under the synergistic action of CdTe@ZnNi-MOF NFs and luminol. The constructed ECL sensor can effectively detect CPF in the range 1.0 × 10 −14 –1.0 × 10 −9 M, and the detection limit was 6.23 × 10 −17 M (3 σ / m ). The constructed sensor was simple and sensitive, and can be used for the determination of CPF in vegetable samples. It not only broadened the application of MOFs in the field of ECL but also provided a new idea for expanding the application of the luminol-O 2 system. Graphical Abstract
研究领域:
分析化学
·
环境科学
✓ 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）