Journal of Materials Chemistry A
·
2021
·Vol. 9
·期 43
·24704-24711
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IF 12.732
Jinchao Li,Wenjie Xu,Wenheng Huang,Jun Long,Jun Liu,Huan Luo,Yaping Zhang,Liangyin Chu
The performance of vanadium redox flow batteries (VRFBs) is largely determined by the membrane as a separator. To address the trade-off issue between the proton conductance and vanadium resistance of sulfonated polyimide (SPI) membranes, novel covalent cross-linked polyfluoro sulfonated polyimide (PFSPI-PAA-X) membranes are developed by designing and synthesizing polyfluoro non-sulfonated diamine and adopting hydrophilic polyacrylic acid (PAA) as the cross-linking agent. The structures, morphology and physico-chemical properties of PFSPI-PAA-X membranes are systematically investigated. PFSPI-PAA-X membranes possess improved chemical stabilities in contrast to the pure PFSPI membrane. Among all PFSPI-PAA-X membranes, the PFSPI-PAA-25 membrane (0.15 Ω cm2) shows the lowest area resistance, which is even a little lower than that of the Nafion 212 membrane (0.16 Ω cm2). And, the PFSPI-PAA-25 membrane also has an extremely low vanadium permeability of 5.90 × 10−9 cm2 min−1, which is two orders of magnitude lower than that of the Nafion 212 membrane (7.53 × 10−7 cm2 min−1). The VRFB performances including the self-discharge time (PFSPI-PAA-25: 52.3 h, Nafion 212: 17.6 h), efficiencies at 60–300 mA cm−2 (PFSPI-PAA-25: CE = 97.3–99.9% and EE = 90.7–73.6%, Nafion 212: CE = 90.9–96.5% and EE = 84.7–72.0%) and peak power density (PFSPI-PAA-25: 451.4 mW cm−2, Nafion 212: 427.9 mW cm−2) of the PFSPI-PAA-25 membrane are all superior to those of the Nafion 212 membrane. Meanwhile, the PFSPI-PAA-25 membrane shows outstanding durability during the 500 times charge–discharge cycle test. Therefore, the as-prepared PFSPI-PAA-25 membrane with excellent cost-performance ratio has a bright future in replacing the Nafion 212 membrane for application in VRFBs.
研究领域:
电化学
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材料科学
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能源存储
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膜技术
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高分子化学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2019
·Vol. 43
·期 28
·11374-11381
·
IF 3.069
Xiao-Bing Yang,Lei Zhao,Kokswee Goh,Xu-Lei Sui,Ling-Hui Meng,Zhen-Bo Wang
A highly proton-/vanadium-selective perfluorosulfonic acid (Nafion) membrane modified by phosphotungstic acid (PWA)-anchored nano Kevlar fibers (NKFs) and nano silica particles (NSP) for a vanadium redox flow battery (VRB) was fabricated through solution casting. The nanohybrid composed of NKFs, NSP and PWA exhibited excellent compatibility with the polymer matrix, and effectively suppressed the vanadium ion crossover. In addition, the anchoring of PWA was of great significance for maintaining the ion exchange capacity and constructing continuous proton transport channels. The optimal Nafion-(NKFs@NSP/PWA) membrane presented a high proton conductivity (0.079 S cm−1) and a low vanadium permeability (6.27 × 10−7 cm2 min−1), resulting in an ion selectivity of 1.26 × 105 S min cm−3, which is much higher than that of recast Nafion (0.34 × 105 S min cm−3). Moreover, the VRB assembled with the modified membrane showed a lower self-discharge rate, higher battery efficiency and superior capacity retention than that with the recast Nafion over a range of current densities from 40 mA cm−2 to 100 mA cm−2.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
高影响因子
ACS Nano
·
2022
·
IF 18.027
Xiaoke Wang,Xixi Zhang,Gang Zhao,Hu Hong,Zijie Tang,Xijin Xu,Hongfei Li,Chunyi Zhi,Cuiping Han
Magnesium ion batteries have potential for large-scale energy storage. However, the high charge density of Mg2+ ions establishes a strong intercalation energy barrier in host materials, causing sluggish diffusion kinetics and structural degradation. Here, we report that the kinetic and dissolution issues connected to cathode materials can be resolved simultaneously using a tetraethylene glycol dimethyl ether (TEGDME)–water hybrid electrolyte. The lubricating and shielding effect of water solvent could boost the swift transport of Mg2+, contributing to a high diffusion coefficient within the sodium vanadate (NaV8O20·nH2O) cathode. Meanwhile, the organic TEGDME component can coordinate with water to diminish its activity, thus providing the hybrid electrolyte with a broad electrochemical window of 3.9 V. More importantly, the TEGDME preferentially amassed at the interface, leading to a robust cathode electrolyte interface layer that suppresses the dissolution of vanadium species. Consequently, the NaV8O20·nH2O cathode achieved a specific capacity of 351 mAh g–1 at 0.3 A g–1 and a long cycle life of 1000 cycles in this hybrid electrolyte. A mechanism study revealed the reversible interaction of Mg2+ during cycles. This organic water hybrid electrolyte is effective for overcoming the difficulty of multivalent ion storage.
研究领域:
储能
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电化学
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材料科学
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电池技术
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2014
·Vol. 39
·期 28
·16123-16131
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IF 2.93
Yufei Wang,Shuanjin Wang,Min Xiao,Shuqin Song,Dongmei Han,Michael A. Hickner,Yuezhong Meng
Novel sulfonated poly (fluorenyl ether ketone) with pendant quaternary ammonium groups (SPFEKA) was successfully synthesized by one-pot copolymerization of bis(4-fluoro-3-sulfophenyl)sulfone disodium salt, 4,4′-difluorobenzophenone, bisphenol fluorene and 2,2′-dimethylaminemethylene-9,9′-bis(4-hydroxyphenyl) fluorene (DABPF). The chemical structures were confirmed by FT-IR, and 1 H NMR. The thermal properties were fully investigated by TGA . The synthesized copolymers SPFEKAs are soluble in aprotic solvents, and can be cast into membranes on a glass plate from their N,N′-dimethylacetamide (DMAc) solution. A new kind of amphoteric ion exchange membrane (AIEM) was obtained by immersed SPFEKA into 1 M sulfuric acid. The proton conductivities of these membranes are comparable to the most reported sulfonated polymers under the same conditions. The permeability of vanadium ions in vanadium redox flow battery (VRB) was effectively suppressed by introducing quaternary ammonium groups for Donnan exclusion effect . AIEM-20% possess a only 4.4% vanadium ion permeability of Nafion 115. Cell performance tests showed that the VRB assembled with AIEM-20% shows the highest coulombic efficiency (CE) at the current density of 50 mA/cm 2 , because of its lowest VO 2+ permeability. In conclusion, these ionomers could be promising candidates for ion-exchange membranes for VRB applications.
研究领域:
材料科学
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电化学
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能源存储
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高分子化学
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膜科学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
·
IF 4.9
Jianing Liu,Yi Huang,Ying Chen,Haobo Ke,Qian Deng,Hua Tang,Jinyan Yang,Shijun Ni
With industry development, water contaminated with vanadium(V) has attracted increasing attention. Various adsorbents have been used to remove V(V); however, reducing V(V) to V(III) or V(IV) with low solubility and toxicity remains a challenge. Herein, a novel layered double hydroxide loading with polyaniline composites (PANI-LDHs) adsorbent was prepared to facilitate V(V) detoxification and elimination. We examined the physicochemical characteristics and confirmed the successful formation of the composite. Some key experimental parameters were evaluated in detail for their potential impact on V(V) removal. The calculated maximum adsorption capacity was 222.22 mg/L with a dosage of only 0.3 g/L under 318 K, which was higher than other adsorbents. More importantly, about 80 % of the absorbed V(V) was reduced and detoxified by reductive nitrogen-containing groups in PANI. In addition, the PANI-LDHs can effectively resist the interference of various coexisting ions. The excellent V(V) removal performance is mainly attributed to the high stability of the inorganic skeleton (LDH) and the high chemical activity of PANI. Dynamics and thermodynamic analysis were also used to study the V(V) adsorption behavior. Finally, the mechanism study suggested that V(V) anions were adsorbed onto the surface of PANI-LDHs via electrostatic attraction or the H-bonding. The adsorbed V(V) was subsequently reduced and immobilized to V(IV) and V(III) oxides by nitrogen-containing groups in PANI, thus achieving the detoxification and removal of V(V). The combination of adsorption and detoxification properties, high adsorption capacity, and good selectivity make PANI-LDHs an ideal candidate for V(V)-containing wastewater treatment.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2021
·
IF 10.588
Jiawei Wen,Ying Sun,Pengge Ning,Gaojie Xu,Shanshan Sun,Zhi Sun,Hongbin Cao
The complete separation of vanadium (V) and chromium (Cr) from chrome vanadium slag is still challenging. Many studies focus on the activity of vanadium, while the effect of the other element chromium and their mutual interaction are ignored. Here, we found that proper concentration of chromium can promote the extraction efficiency of vanadium. The extraction of V and Cr with various mass ratios ranging from 8:1–4:3 at different initial pH values using primary amine N1923 were studied. The extraction efficiency of V reached nearly 100%, while none of Cr was extracted when the mass ratio of Cr and V is 0.5 under proper pH. Through the dynamic monitoring of species evolutions during extraction, the transformation of the two metals and advantage extracted species were analyzed. Cr would transfer H + for the combination of V 3 O 9 3- /V 4 O 12 4- , providing a great contribution to the continuous extraction of V. The real leachate was applied and 99.9% vanadium pentoxide was produced at a scale of 50 L/h. This paper offers deep insights of the separation of similar metal elements, and guide sustainable vanadium recovery from hazardous waste .
研究领域:
冶金学
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环境科学
✓ 已验证
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
·
IF 8.1
Hongzhan Lv,Liwen Zhang,Xiaoli Xi,Zuoren Nie
With the widespread expansion of titanium applications and its significant increase in usage, the issue of recycling titanium resources after consumption has emerged. Focusing on titanium alloys with high usage, such as TC4 (Ti-6Al-4V), this article proposes a titanium separation and recovery method based on molten salt electrolysis. This method thoroughly analyzes the characteristics of elements in TC4 and electrochemical principles, ensuring that vanadium in the TC4 alloy does not undergo electrochemical dissolution when the electrolysis potential is below 0.3 V vs Pt. Subsequently, through electrochemical analysis, it was discovered that the precipitation of aluminum ions is influenced by concentration. Therefore, by controlling the concentration of aluminum in the eutectic molten salt, such as increasing the electrolyte concentration and shortening the electrolysis time, the precipitation of aluminum can be effectively avoided. Under the experimental conditions mentioned above, vanadium elements deposit at the bottom of the crucible in the form of anode slime, while aluminum dissolves and remains in the electrolyte. Meanwhile, titanium ions in the cathode region undergo electron reduction and deposit in the cathode area in the form of titanium, thus achieving precise separation of alloy elements. Experimental verification shows that the purity of the obtained titanium reaches 99.17 atomic percent. Therefore, this molten salt electrolysis method, which combines the physical properties of alloy elements with electrochemical principles, not only provides a new perspective for the separation and recovery of titanium and other critical metals, but also offers new research directions for the recovery technology of other alloy elements.
研究领域:
冶金学
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材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Jianqi Cao,Lei Zhang,Wanlin Wang,Daoyuan Huang,Yongqi Sun
As a dominant resource for vanadium extraction, roasting of vanadium-bearing slags involves the destruction of vanadium-containing phases, mainly including iron-vanadium spinels and liquid phase, and the formation of soluble vanadate. Extraction of vanadium from iron-vanadium spinels determines the efficiency of the whole process due to their ultrastabilities. Here the phase and composition evolutions of iron-vanadium spinels containing chromium were investigated by both advanced experimental characterizations (EPMA, XRD and XPS, etc.) and thermodynamic analysis. The roles of roasting conditions were clarified, including roasting temperature, time and the presence of chromium. It was found that, upon roasting, the iron-vanadium spinels underwent a phase transition to form two distinct phases, namely a vanadium-enriched phase and a Me 2 O 3 solid solution phase. A relatively high roasting temperature with a relatively long roasting time could enhance the completeness of the roasting reaction and improve the separation of vanadium from iron and chromium. The evolution of iron-vanadium spinels with the current compositions (n(FeO): n(V 2 O 3 ): n(CaO): n(Cr 2 O 3 ) = 4: 1: 2: 0.2) followed a three-step mechanism under the current roasting conditions, i.e., an initial step of the oxidation decomposition of spinels, a reaction between CaO and V 2 O 5 to form CaV 2 O 6 , and a final reaction between residual CaO and CaV 2 O 6 to form a Ca 2 V 2 O 7 phase. Moreover, the presence of chromium resulted in an increase in the Fe 2 O 3 concentration within the vanadium-enriched phase due the formation of a solid solution with an infinite miscibility between Cr 2 O 3 and Fe 2 O 3 . The findings of this study offer not only scientific insight with regard to the evolution of iron-vanadium spinels upon roasting but also significant guidance for the optimization of roasting conditions toward target vanadium extraction from iron-vanadium spinels.
研究领域:
冶金学
·
材料科学
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产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2019
·Vol. 91
·期 2
·302-309
·
IF 1.986
Zou Jian,Xiao Lei,Zhu Li,Chen Xuanyan
In this study, monoclinic vanadium dioxide (VO 2 ) nanoparticles were synthesized by one-step rapid hydrothermal treatment of a sol precursor, and the obtained products were examined using various analytical methods. Results indicated that monoclinic VO 2 nanoparticles could be obtained using ammonium metavanadate as the precursor at a high concentration of 2.37 M and the shortest duration was only 1 h. X-ray diffraction (XRD) revealed that VO 2 presented high crystallinity with a pure monoclinic phase. Phase transition latent heat of VO 2 was estimated to be 45.5 J/g. Furthermore, VO 2 powders were mostly composed of granules with a size distribution ranging from 20 nm to 100 nm. Monoclinic VO 2 nanoparticles were derived from the decomposition of the intermediate (NH 4 ) 2 V 4 O 9 .
Monoclinic vanadium dioxide (VO 2 ) nanoparticles can be synthesized by one-step rapid hydrothermal treatment of sol precursor with high concentration.
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
JOURNAL OF MEMBRANE SCIENCE
·
2019
·
IF 7.015
Qing Dai,Wenjing Lu,Yuyue Zhao,Huamin Zhang,Xiangxue Zhu,Xianfeng Li
A zeolite composite membrane (ZCM) was designed and fabricated via a simple versatile and scalable method. A thin layer of ZSM-35 flakes with pore size between hydrated protons and vanadium ions was fixed on the poly(ether-sulfone)/sulfonated poly(ether-ether-ketone) (PES/SPEEK) porous substrate by in-situ interfacial polymerization. The ZSM flake layer can perfectly separate hydrated vanadium ions and protons, therefore, show very impressive performance for vanadium flow batteries (VFBs). As a result, a VFB assembled with an optimized ZCM exhibited a columbic efficiency more than 99% and energy efficiency of over 91% at a current density of 80 mA cm -2 , which is among the highest performance ever reported. Furthermore, the energy efficiency can reach 81.6% at a very high current density of 200 mA cm -2 and keep stable for 1000 cycles at a current density of 180 mA cm -2 . This method opened a door toward the large-scale production of highly selective composite membranes for flow batteries.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
HYDROMETALLURGY
·
2019
·
IF 3.465
Xuexin Chen,Hui Wang,Baijun Yan
In order to recover vanadium from vanadium-bearing black shale efficiently, a hydrometallurgical process is developed in this paper to treat the concentrate beneficiated from stone coal ore, in which the vanadium mainly occurs in the form of Fe 3- x V x O 4 spinel. At the first step, the leaching behaviors of Fe and V from the concentrate by using sulfuric acid solution are investigated in detail. The extraction rates of vanadium and iron could reach 92.5% and 98.5% respectively under the optimum leaching conditions of leaching temperature of 90 °C, sulfuric acid concentration of 25 wt%, leaching time of 90 min, L/S mass ratio of 30 and stirring speed of 600 rpm. Secondly, the iron impurity in the pregnant solution is removed efficiently by the precipitation method with Fe 2 O 3 as nucleating agent. The effect of pH value, the amount of Fe 2 O 3 nucleating agent and the precipitating time on the removal of iron and losing of vanadium are systematically investigated, and thereby >99.7% iron impurity can be removed with the loss rate of vanadium not higher than 2.5%. Finally, vanadium is precipitated from the purified leach solution as ammonium poly-vanadate by adding ammonium sulfate , and then the product of V 2 O 5 is obtained by calcining the ammonium poly-vanadate. The purity of V 2 O 5 powder can reach 92.0% approximately.
研究领域:
冶金学
·
无机化学
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产品关联
DOI
高影响因子
MOLECULES
·
2020
·Vol. 25
·期 6
·1448
·
IF 3.267
Xi Huang,Zhenxiong Ye,Lifeng Chen,Xujie Chen,Caocong Liu,Yuan Yin,Xinpeng Wang,Yuezhou Wei
Every year, a large quantity of vanadium-containing wastewater is discharged from industrial factories, resulting in severe environmental problems. In particular, V(V) is recognized as a potentially hazardous contaminant due to its high mobility and toxicity, and it has received considerable attention. In this study, a silica-supported primary amine resin (SiPAR) was prepared by in-situ polymerization, and the V(V) adsorption from the solution was examined. The as-prepared resin exhibited fast adsorption kinetics, and it could attain an equilibrium within 90 min for the V(V) solution concentration of 100 mg/L at an optimum pH of 4, whereas the commercial D302 resin required a treatment time of more than 3 h under the same conditions. Furthermore, the maximum adsorption capacity of the resin under optimum conditions for V(V) was calculated to be 70.57 mg/g. In addition, the kinetics and isotherm data were satisfactorily elucidated with the pseudo-second-order kinetics and Redlich–Peterson models, respectively. The silica-based resin exhibited an excellent selectivity for V(V), and the removal efficiency exceeded 97% in the presence of competitive anions at 100 mmol/L concentrations. The film mass-transfer coefficient (kf) and V(V) pore diffusivity (Dp) onto the resins were estimated by mathematical modeling. In summary, this study provided a potential adsorbent for the efficient removal of V(V) from wastewater.Keywords:pentavalent vanadium;removal;silica-supported resin;mathematical modeling
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
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