SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Yifan Zhang,Xianwei Hu,Jiaxin Yang,Liyu Chen,Wenju Tao,Fengguo Liu,Zhongning Shi,Zhaowen Wang
Aluminum-vanadium intermediate alloy is a significant raw material for the fabrication of high-performance titanium alloys . In the present study, the electrochemical behavior of NaVO 3 on a solid molybdenum and liquid aluminum electrode is systematically investigated by cyclic voltammetry (CV) and square wave voltammetry (SWV) in the NaF-KF-AlF 3 molten salt and the formation mechanism of Al-V intermetallic compounds is emphatically analyzed. The results show that the electrochemical reduction of VO 3 − on the solid molybdenum electrode is a multi-step process and low-valence vanadium oxide (V 2 O 3 ) is obtained. In contrast, the electrochemical reduction of VO 3 − to V 2 O 3 on liquid aluminum electrode is through one-step process and the deposition potential is more positive than that on molybdenum electrode owing to the depolarization effect of the liquid aluminum electrode. In addition, Al-V intermetallic compounds are obtained on the liquid aluminum electrode by potentiostatic electrolysis. The reduction process of VO 3 − on the liquid aluminum electrode is described as: the electrochemical process is started by the direct electro-reduction of VO 3 − to V 2 O 3 , which is further converted to Al-V intermetallic compounds under the combined effect of electrochemical and aluminothermic reduction, with the latter playing a dominant role.
研究领域:
冶金学
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材料科学
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DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-12
·
IF 15.7
Tian Momang,Meng Ke-Juan,Xiong Kunyu,Hussain Iftikhar,Ma Xinwen,Zhang Kaili
Nanothermite has gained significant attention for its exceptional energy release rate and reactivity, making it a promising material for energetic applications. However, nanoparticle agglomeration significantly hinders its energy release efficiency. To overcome this challenge, we developed an innovative bottom-up strategy and a straightforward preparation method to construct a hierarchical Al/CuO/V 2 C nanocomposite. This is achieved through the ordered self-assembly of Al and CuO nanoparticles in an ethanol suspension, using V 2 C MXene as a template. Our findings show that the Al/CuO/V 2 C nanocomposite exhibits distinct morphologies based on V 2 C concentration: nanosheets at lower concentrations and microspheres at higher concentrations. CuO and Al nanoparticles form the first and second layers outside the V 2 C, respectively, due to the interplay between electrostatic forces and covalent Cu-O-V bonds. This unique structure, along with high reactivity of V 2 C, enables complete Al oxidation, achieving a heat release of 3156.2 J g -1 with a 10 wt% V 2 C addition—seven times greater than the Al/CuO control group. The concentration-dependent structure allows for tunable energetic performance, from a rapid 3-ms deflagration to a prolonged 16-ms combustion. Reduced gas release enhances safety, paving the way for applications in microinitiators and advancing nanothermite technology.
研究领域:
纳米材料
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高能材料
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自组装
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燃烧技术
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微型点火器
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DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2017
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IF 6.395
Lesi Zhang,Ling Ling,Min Xiao,Dongmei Han,Shuanjin Wang,Yuezhong Meng
A novel self-assembled composite membrane , Nafion-[PDDA/ZrP] n with nacre-like nanostructures was successfully fabricated by a layer-by-layer (LbL) method and used as proton exchange membrane for vanadium redox flow battery applications. Poly(diallyldimethylammonium chloride) (PDDA) with positive charges and zirconium phosphate (ZrP) nanosheets with negative charges can form ultra-thin nacre-like nanostructure on the surface of Nafion membrane via the ionic crosslinking of tightly folded macromolecules. The lamellar structure of ZrP nanosheets and Donnan exclusion effect of PDDA can greatly decrease the vanadium ion permeability and improve the selectivity of proton conductivity . The fabricated Nafion-[PDDA/ZrP] 4 membrane shows two orders of magnitude lower vanadium ion permeability (1.05 × 10 −6 cm 2 min −1 ) and 12 times higher ion selectivity than those of pristine Nafion membrane at room temperature. Consequently, the performance of vanadium redox flow batteries (VRFBs) assembled with Nafion-[PDDA/ZrP] 3 membrane achieved a highly coulombic efficiency (CE) and energy efficiency (EE) together with a very slow self-discharge rate. When comparing with pristine Nafion VRFB, the CE and EE values of Nafion-[PDDA/ZrP] 3 VRFB are 10% and 7% higher at 30 mA cm −2 , respectively.
研究领域:
材料科学
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能源技术
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DOI
高影响因子
Journal of Energy Storage
·
2024
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IF 8.9
Wenheng Huang,Jun Long,Huiting Li,Liang Chen,Jinchao Li,Qianqian Liang,Xuedan Chen,Zhengjin Yang,Yingze Song,Yaping Zhang
In this work, a new branched trianhydride monomer 1,3,5-tris(4-naphthyloxy-1,8-diacid) phthalic anhydride is established for improving the chemical/dimensional stability and proton conduction of the branched sulfonated polyimide (BSPI) membrane for application in vanadium flow battery (VFB). Compared with linear SPI-60 membrane containing conventional dianhydride monomer 1,4,5,8-naphthalenetetra-carboxylic dianhydride, BSPI-60 membrane exhibits remarkable resistance to vanadium ions , proton conduction and structural stability . Besides, the challenge of simultaneously improving vanadium ions resistance and proton conductance is tackled. The proton selectivity of BSPI-60 membrane achieves 1.11 × 10 5 S·min/cm 3 , which is 2.8 and 2.5 times higher than both SPI-60 (0.39 × 10 5 S·min/cm 3 ) and commercial Nafion 212 (0.44 × 10 5 S·min/cm 3 ) membranes, respectively. At the same time, BSPI-60 membrane exhibits higher coulomb efficiencies (97.2 %–99.3 %) and energy efficiencies (85.6 %–69.5 %) compared those of SPI-60 and Nafion 212 membranes at 100–300 mA/cm 2 . Remarkably, the 500 cycles of BSPI-60 membrane at 140 mA/cm 2 are also stably executed. The internal reasons for enhanced chemical/dimensional stabilities and proton conduction of BSPI-60 membrane are clarified from theoretical calculations with mean square displacement value, fractional free volume and natural bond orbital charge via density functional theory and molecular dynamics simulation . Our study encompasses not only the synthesis of a novel branched trianhydride monomer but also the development of a BSPI membrane with a unique molecular structure specifically designed for VFB applications.
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
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
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2024
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IF 2.8
Bo Wang,Qiaowen Yang,Ting Li,Sifan Cui,Pengqiang Feng,Xuan Hou
BACKGROUND Selective catalytic reduction (SCR) can effectively remove NO x from flue gas in a coal-fired power plant. As the core of SCR technology, the catalyst has a limited lifespan. The process of reducing acid leaching and roasting water leaching can efficiently extract vanadium and tungsten from spent SCR catalyst. For vanadium recovery in solution, the traditional vanadium precipitation process by NH 4 Cl has the disadvantages of consuming high precipitant dosage and producing large amounts of waste water. RESULTS This study focused on the vanadium precipitation process using a solution containing vanadium obtained from adopting some steps to handle the spent SCR catalyst. First, melamine was screened out as the vanadium precipitant. Then, the vanadium precipitation conditions were optimized as follows: solution pH value of 1.0, n (C 3 H 6 N 6 )/ n (V) = 0.8, 110 °C and 30 min. Under the best precipitation conditions, the vanadium precipitation efficiency of melamine can reach 99.32%. Finally, the mechanisms of vanadium precipitation by NH 4 Cl and melamine were discussed, respectively. CONCLUSION The results showed that the vanadium precipitation process by NH 4 Cl followed the chemical reactions between NH 4 + and vanadium ions, while the vanadium precipitation process by melamine followed the redox and complexation reactions which essentially belonged to the types of chemical adsorption. The vanadium precipitation product was roasted at 550 °C for 2 h to obtain the vanadium product. The main component of the vanadium product was V 2 O 5 , with a purity of 93.27 wt%. The total recovery efficiency of vanadium from spent SCR catalyst was 78.24%. © 2024 Society of Chemical Industry (SCI).
研究领域:
环境科学
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化学工程
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材料科学
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DOI
高影响因子
SOLVENT EXTRACTION AND ION EXCHANGE
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2023
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IF 2
Lili Cui,Jungang Cao,Shihui Jiao,Guangsheng Pang,Zhonglin Wei
A selective extraction process for recovering vanadium (IV) over chromium was proposed with use of a mixed extractant consisting of di(2-ethylhexyl) phosphate (D2EHPA) and tri-n-butyl phosphate (TBP). The influence of various factors, which included the initial aqueous pH value, the concentration of leach solution and D2EHPA, phase ratio (O/A), extraction equilibrium time and extraction temperature in the extraction process on the separation of V and Cr was investigated. Under the condition of the optimum extraction, vanadium extraction was above 94.0%. Meanwhile, under the optimum stripping conditions, the vanadium stripping was above 93.0% utilizing 1.5 mol/L sulfuric acid as the effective stripping reagent. The regeneration and reusability of the loaded organic phases after stripping were discussed. In addition, continuous three-stage extraction and stripping strategy indicated that the aggregate loss of vanadium was 0.885% and that the purity of vanadium was more than 99.9%. Under the condition of the optimum precipitation, when the pH value of the stripping solution was adjusted to 7.0 with ammonia water, the precipitation efficiency reached 99.93%. The calcination conditions (above 680 °C in air) were finally determined by TG-DTA and TG-MS experiments, and the V2O5 obtained by calcination was characterized by XRD. Additionally, a method for detecting impurity elements in vanadium matrix without interference was established. The recovery technology has practical significance in enlarging production scale, reducing specific energy consumption and cost, and realizing automatic control in vanadium leaching process.
研究领域:
冶金学
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化学工程
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DOI
高影响因子
ELECTROCHIMICA ACTA
·
2024
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IF 5.5
Nianben Zheng,Xuemei Qiu,Shengqian Jin,Zhangnan Xu,Mingyu Zhou,Zexin Zhou,Tian Zhou,Zhiqiang Sun
The electrolyte employed in the vanadium redox flow battery (VRFB) is typically produced on an industrial scale through a secure and contaminant-free electrolysis process. However, the electrolysis rate is relatively sluggish, leading to elevated energy consumption. Herein, we propose a cost-effective method for electrolytic production of V(IV) electrolytes with carboxyl-functionalized multi-walled carbon nanotubes (MWCNTs-COOH) as the electrocatalyst and explore their effects on the electrolysis process. The results indicate that adding MWCNTs-COOH nanoparticles enhances the reactive sites of the electrode, thus improving the electrochemical activity of the electrolyte. The 0.1 wt% nanoparticle demonstrates the optimal catalytic performance for reducing V(V) to V(IV). Compared to the traditional electrolysis method, the proposed approach exhibits a 6.67 % increase in electrolysis rate, a 15.57 % reduction in energy consumption, and a notable relief in electrode corrosion. Furthermore, cyclic charge/discharge experiments illustrate that the prepared nanofluidic electrolyte exhibits superior performance in terms of voltage efficiency, Coulombic efficiency, energy efficiency, and discharge capacity retention. This invention offers a novel concept for vanadium electrolyte preparation, which reduces energy consumption and cost and improves the system's energy efficiency, showing great promise for practical VRFB applications.
研究领域:
材料科学
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电化学工程
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DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2021
·Vol. 223
·期 8
·2100338
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IF 2.527
Chao Qu,Hongzhang Zhang,Changsheng Wang,Xianfeng Li
A membrane with low vanadium ion permeability and excellent electrochemical stability is crucial for a vanadium flow battery (VFB). Herein, a highly stable anion exchange membrane based on a bi-guanidinium crosslinking quaternized poly(arylene ether sulfone) (PSF) is reported. The positively charged guanidinium groups can not only form continuous and smooth ion transport channels but also prevent the mutual penetration of vanadium electrolyte at positive and negative sides, respectively, based on the Donnan exclusion effect. Moreover, the crosslinking structure endows the membrane high mechanical strength to meet the requirements of the harsh environment of VFBs. As a result, the anion exchange membrane fabricated by the poly(arylene ether sulfone) crosslinked with bi-guanidinium (BG-PSF) shows an impressive VFB performance with a coulombic efficiency of 99.8% and an energy efficiency of above 85.8% at a current density of 80 mA cm −2 , which is much higher than that of Nafion115. Furthermore, this battery can continuously work for over 200 cycles at a current density of 80 mA cm −2 , indicating good stability of the membrane. Therefore, the rationally designed BG-PSFs are promising for VFB applications.
研究领域:
材料科学
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能源技术
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DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2020
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IF 8.247
Ying Liu,Lingyang Liu,Long Kang,Fen Ran
Vanadium nitride has a large potential window of 1.2 V and a high capacitance in the aqueous electrolyte attributed to vanadium oxides existed on its surface. However, these vanadium oxides, to be precise, V 5+ -containing oxides existed on vanadium nitride surface, always gradually dissolve in alkaline electrolyte as cycle progress goes, which largely affects cycling stability of the material. In this paper, we prepare imidazole-Vanadium-Organic Frameworks (imi-V-MOFs) as precursor to synthesize vanadium nitride containing single VO 2 on material surface by method of facile chemical reaction. The prepared vanadium nitride shows a wide operating potential of 1.2 V and a capacitance of 149.5 F/g. The most amazing thing is that it has good cycle stability with capacitance retention of 85% after 1, 000 cycles at 1 A/g.
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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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Jun Long,Wenheng Huang,Huiting Li,Xiyang Liu,Jinchao Li,Liang Chen,Qin Chen,Jijun Chen,Zhengjin Yang,Yaping Zhang
The membrane always plays as a crucial component of vanadium flow battery (VFB), and its proton selectivity and stability determine battery efficiencies and life. Herein, a series of permselective cross-linked sulfonated polyimide (PFSPI-DNBC) membranes are constructed by using crown ether with proper cavity size as cross-linker to break the trade-off effect between proton conductance and vanadium ions blocking. In contrast to commerical Nafion 212 membrane, the as-optimized PFSPI-DNBC-15 membrane reveals outstanding comprehensive properties: same area resistance (0.21 Ω cm 2 ), excellent vanadium ions blocking (0.44×10 −7 cm 2 min −1 ) and 15.91 times higher proton selectivity (5.41×10 5 S min cm −3 ). Furthermore, the PFSPI-DNBC-15 membrane shows higher Coulomb efficiencies ( CE s: 97.45%–98.35%) and energy efficiencies ( EE s: 68.58%–87.76%) compared with Nafion 212 membrane ( CE s: 92.74%–95.26%; EE s: 67.39%–81.28%) at 100–280 mA cm −2 . Exhilaratingly, the PFSPI-DNBC-15 membrane shows remarkable chemical structural and morphological stabilities over 2280 VFB cycles at 180 mA cm −2 . The internal reasons of improved stability of PFSPI-DNBC-15 membrane are described by simulation calculations. To sum up, the PFSPI-DNBC-15 membrane possesses a bright application prospect in VFB.
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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DOI
高影响因子
ACS Applied Materials & Interfaces
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2024
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IF 8.3
Jun Long,Wenheng Huang,Huiting Li,Liang Chen,Jinchao Li,Jijun Chen,Aibing Lu,Yaping Zhang
Membrane with remarkable proton conductance and selectivity plays a key role in obtaining high vanadium flow battery (VFB) performance. In this work, the trade-off effect between proton conductance and vanadium ion blocking was overcome by the introduction of a cross-linking structure to prepare covalent cross-linked fluorine-containing sulfonated polyimide (CFSPI-PVA) membranes. Herein, the CFSPI-PVA-15 membrane possesses excellent comprehensive properties, including acceptable area resistance (0.21 Ω cm2), lower vanadium ion permeability (0.76 × 10–7 cm2 min–1), and remarkable proton selectivity (3.11 × 105 min cm–3) compared with the commercial Nafion 212 membrane. At the same time, the CFSPI-PVA-15 membrane exhibits higher coulomb efficiencies (97.26%–99.34%) and energy efficiencies (68.65%–88.11%) and a longer self-discharge duration (29.2 h) in contrast with the Nafion 212 membrane. Moreover, 500 cycles of the CFSPI-PVA-15 membrane at 160 mA cm–2 are also stably executed. The internal reasons for the improved chemical stability of the CFSPI-PVA-15 membrane are clarified from theoretical calculations with the mean square displacement value and fractional free volume. Therefore, the CFSPI-PVA-15 membrane exhibits great potential for application in VFB.
研究领域:
材料科学
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能源化学
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Yongzheng Jia,Yu Qing,Baoyan Feng,Yiwei Zhong,Lei Dai,Mingyong Wang
Green separation and efficient extraction of vanadium and chromium from vanadium-chromium leaching solution are serious challenges for the utilization of chrome-vanadium slag. A green sucrose reduction-H 2 O 2 selective oxidation route is proposed for deep separation of vanadium and chromium from vanadium-chromium leaching solution based on different redox properties. Eh-pH diagram of V-Cr-H 2 O system and existence forms of vanadium and chromium ions are calculated. Obvious difference of redox properties between V(V) and Cr(VI) exists in acidic environment. The dependences of selective separation on pH for reduction, temperature, m (sucrose) /m (Cr(VI)) and n (H2O2) /n (V(V)) are studied. The concentration ratio of vanadium to chromium in solution after selective separation of chromium decreases from 1.6 to 0.06. The extraction ratios of Cr 2 O 3 and V 2 O 5 are 96.3% and 93.8%, respectively. The redox behavior of V(V) and Cr(VI) is revealed. Cr(VI) and V(V) are reduced to Cr(Ⅲ) and V(IV) by 5-hydroxymethylfurfural, a hydrolysate of sucrose, and then V(IV) is selectively oxidized to V(V) by H 2 O 2 . Cr 2 O 3 ·n(H 2 O) and ammonium polyvanadate obtained by hydrolysis and ammonium precipitation are calcined to Cr 2 O 3 and V 2 O 5 , respectively. Cr 2 O 3 with the purity of 99.4% can be used as high-quality pigment. The purity of V 2 O 5 meets the requirements of YB/T 5304–2011 for 98 V 2 O 5 .
研究领域:
冶金工程
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环境科学
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产品关联
DOI
高影响因子
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