JOURNAL OF ALLOYS AND COMPOUNDS
·
2013
·
IF 2.39
Pei Pei Yuan,Bin Hong Liu,He Peng Zhu,Wei Yuan Pan,Zhou Peng Li
In this work, the composites of LiBH 4 and AlF 3 were prepared and their hydrogen storage properties were investigated. The AlF 3 addition to LiBH 4 resulted in significant decreases in dehydrogenation temperature. All the x LiBH 4 + AlF 3 ( x = 1, 2, 3, 5) composites started to release hydrogen from about 100 °C. The dehydrogenation of the composites was accomplished through several steps, depending on the molar ratio of LiBH 4 to AlF 3 . A new phase Li 3 AlF 6 was formed during the first dehydrogenation step, which further reacted with LiBH 4 . AlB 2 was formed only at temperatures higher than 300 °C. Li 2 B 12 H 12 was detected as an intermediate. The dehydrogenation reactions have significantly reduced and thus favorable enthalpy changes. However, the reversibility of the composites needs to be improved.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Results in Chemistry
·
2023
·
IF 2.3
Hengwei Yan,Ye Kuang,Yonghui Yang,Jiyan Gao,Zhanwei Liu
Because direct roasting of aluminum fluoride hydrate will hydrolysis, resulting in higher alumina content in aluminum fluoride products. To solve this problem, a two-step process for the preparation of anhydrous AlF 3 from AlF 3 ·3H 2 O and NH 4 HF is described in this paper. First, AlF 3 ·3H 2 O was dried at 220 ℃ for 9–12 h, and then NH 4 HF (the mass ratio of AlF 3 ·3H 2 O to NH 4 HF was 1:20) was added, and the mixture was roasted from room temperature to 650 ℃. The results showed that the hydrolysis of aluminum fluoride can be avoided effectively by the two-step roasting method with NH 4 HF, the purity of the anhydrous AlF 3 was 99.8 wt%, and the concentration of alumina, the main impurity, was less than 0.1 wt%.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2019
·
IF 2.781
Wenfeng Han,Haili Wang,Bing Liu,Xiliang Li,Haodong Tang,Ying Li,Huazhang Liu
With Al(NO 3 ) 3 ·9H 2 O as the Al precursor and PVDF as the fluorine source, freestanding AlF 3 sub-microspheres were fabricated following calcination , without the involvement of corrosive HF solution. With the varying of Al(NO 3 ) 3 ·9H 2 O to PVDF weight ratio, θ -AlF 3 and β -AlF 3 , α -AlF 3 were obtained respectively. The formation mechanism, morphology, surface properties and catalytic activities for the dehydrofluorination of 1,1,1,2-tetrafluoroethane to trifluoroethylene were investigated. During the fabrication process, Al(NO 3 ) 3 interacts with O=C bond in DMF. Meanwhile, DMF further interacts with CH 2 species in PVDF. Following calcination , PVDF decomposes to CO 2 and HF fluorinating Al species to AlF 3 . The growth of AlF 3 crystal and particle are confined by PVDF. Consequently, θ -AlF 3 , β -AlF 3 and α -AlF 3 are achieved. At 450 °C, HFC-134a conversion of 23% and reaction rate of 1.9 mmol g −1 h −1 are approached over θ -AlF 3 catalyst. The reaction rate is almost 3 times higher than that of β -AlF 3 and is 40% higher than that of high surface area α -AlF 3 prepared by sol-gel method. No significant deactivation is observed in time on stream of 40 h. The stability is attributed to the interaction of AlF 3 with carbon frame work. The present study provides a scalable and facile synthesis route for AlF 3 spheres with controllable phase structures.
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
Materials Today Communications
·
2023
·
IF 3.8
Jiaming Li,Youjian Yang,Wenju Tao,Zhaowen Wang,Jiangyu Yu,Jiaxin Yang,Zhibo Liu
As China's aluminum electrolysis industry expanded its production capacity, it produced a large amount of bath materials– cryolite based molten salt, which is not utilized fast enough and piled up in aluminum factories. It is of great significance to find a proper way to process the accumulated bath materials. Through the method introduced in this paper, aluminum fluoride can be produced from cryolite-based electrolyte and fed back into the aluminum electrolysis cell as a necessary additive. This method includes four steps: Calcination of crystalline aluminum nitrate with cryolite. Cryolite and crystalline aluminum nitrate are mixed and preheated. The main chemical reaction that occurs in this step will produce sodium nitrate (NaNO 3 ), β-aluminum fluoride (β-AlF 3 ), chiolite (Na 5 Al 3 F 14 ) and the aluminum hydroxyfluoride hydrate (AHF). After calcination, the products are washed with water to separate soluble NaNO 3 from the other products. The insoluble products obtained after washing are calcined with ammonium bifluoride to convert AHF into AlF 3 . The mixture obtained after preheating is then washed with an aqueous solution of aluminum salt (such as Al(NO 3 ) 3 ) to remove Na 5 Al 3 F 14 . Aluminum fluoride of high purity is obtained in the end. Calcination step is the most important among the four steps. The effects of calcination temperature (85 – 135 ℃) and molar ratio of crystalline aluminum nitrate to cryolite (0.5 – 2) on the conversion rate of cryolite were studied. The experimental results show that the highest conversion rate of cryolite can reach 97.03%. Through SEM, EDS , ICP and other analysis methods, it was found the final products contained more than 98.8 wt% aluminum fluoride and less than 0.4 wt% sodium, and the average particle size of aluminum fluoride is approximately 15 – 20 µm.
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
CATALYSIS COMMUNICATIONS
·
2020
·
IF 3.612
Jiaqin Lu,Wenfeng Han,Wei Yu,Yongnan Liu,Hong Yang,Bing Liu,Haodong Tang,Ying Li
Aluminum fluoride (AlF 3 ) is a typical catalyst for dehydrofluorination of hydrofluorocarbons (HFCs) to fluoroolefins with high heat of reaction. Consequently, heat supply and sintering are the key challenges for AlF 3 -based catalysts. Herein, SiC with high thermal conductivity and resistance to HF corrosion is suggested as a candidate support of AlF 3 catalyst. The interaction between AlF 3 and SiC leads to uniform distribution of the catalytic phase, and as a result of this, AlF 3 /SiC exhibits high catalytic activity and stability for the dehydrofluorination of 1,1-difluoroethane to vinyl fluoride. This study proposes a novel catalyst support (SiC) for strong endothermic catalytic reactions involving HFCs for the first time to the best of our knowledge.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
MINERALS ENGINEERING
·
2022
·
IF 5.479
Shaohua Wu,Wenju Tao,Wang Han,Hui Ge,Liyu Chen,Jiaxin Yang,Yanchen Zheng,Jingui He,Youjian Yang,Zhaowen Wang
Anode cover material holds marked importance owing to its effect of maintaining the thermal balance of aluminum reduction cells, and is categorized as solid waste because of its continuous accumulation. However, cover materials contain large amounts of alumina and fluoride; thus, can be considered for strategic resource recovery. This research has developed a process for separating alumina and recovering aluminum fluoride from anode cover materials by aluminum salt solution leaching . In the present work, the effects of different factors on the leaching behaviors of sodium and fluoride during aluminum salt solution leaching were investigated. The results showed that 98.1 % sodium and 95.1 % fluoride were extracted when the Al 3+ concentration was 2.5 mol/L, the liquid to solid ratio was 20 mL/g, and the stirring speed was 300 rpm at 90 °C for 2 h. Aluminum and fluoride were then precipitated as aluminum hydroxyfluoride hydrate (AHF) from the leachate. The aluminum fluoride (AlF 3 ) product with high purity was obtained by calcining AHF precipitation, and the average particle size was 66.1 μm. This work demonstrates significant application potential on green recycling of anode cover materials and realize a high-value utilization of aluminum and fluoride resources. This plays a crucial role in the life cycle assessment (LCA) of the anode cover material.
研究领域:
冶金学
·
环境科学
·
资源回收
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Jiaxin Yang,Wenju Tao,Jiaming Li,Lingyu Kong,Shaohua Wu,Jingui He,Zhaoshun Liu,Yu Sun,Zhaowen Wang
Low energy consumption and environmentally friendly recycling methods can extract high-added value and high-demand elements from retired waste fluorinated aluminum electrolytes (RWE-Al), which is crucial for alleviating resource shortages and environmental hazards. This study aims to develop a method for recovering fluorine and aluminum from RWE-Al through calcium leaching transformation combined with acid leaching. Compared to the traditional high-temperature roasting transformation and high-concentration alkali-metal-salt leaching process, this new process only involves one step of low-temperature leaching, purification of fluorine, carbonization of excess calcium, and evaporation extraction of aluminum, avoiding the generation of high energy consumption and secondary hazardous waste (F-containing liquid/ residue). Fluorine and aluminum are effectively separated and purified with extraction rates exceeding 96%. The effects of leaching temperature, CaO addition coefficient, liquid–solid ratio, and leaching time on the leaching process were systematically studied. The effects of acid concentration, liquid–solid ratio, time, and temperature on the acid-leaching process were also investigated. In summary, the comprehensive utilization of RWE-Al by this new process has proved to be feasible.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Chemistry
·
2023
·
IF 7.3
Tongyu Liu,Yaoguo Huang,Linlin Chen,Hui Zhang,Caifu Dong,Ming Wang,Yali Zhang
Vanadium oxide (V 2 O 5 ) cathode material , possessing abundant reserves and high theoretical capacity, has been extensively researched in aqueous zinc ion batteries (ZIBs). However, its electrochemical performance is significantly hindered by insufficient electronic conductivity, vanadium dissolution into electrolyte, and slow diffusion kinetics. In this study, the V 2 O 5 micro-flower was first synthesized by a solvothermal method, and then modified by coating with AlF 3 passivation layer, forming AlF 3 @V 2 O 5 hybrid material . Impressively, AlF 3 @V 2 O 5 exhibits excellent electrochemical and kinetic properties due to the special structure of V 2 O 5 and the interfacial protection of AlF 3 . An exceptional rate property (325 mAh g −1 at 0.1 A g −1 , 188 mAh g −1 at 15 A g −1 ) as well as extraordinary cycling stability with 89.3% capacity retention after 6000 cycles at 10 A g −1 can be attained with 2 wt% AlF 3 addition (that is AF-2@V 2 O 5 ). The computation based on density functional theory (DFT) suggests that AlF 3 coating can reduce the interlayer electrostatic interaction and adsorption energy barrier between the intercalated Zn 2+ and V 2 O 5 host, thereby enabling fast redox kinetics. This study showcases the efficacy of interfacial modification of passivated coatings and presents an influential approach for material design in ZIBs .
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2018
·
IF 4.439
Xue Li,Yan-Rong Liu,Wen-Min Liao,Ai-Ping Jia,Yue-Juan Wang,Ji-Qing Lu,Meng-Fei Luo
Catalytic propane combustion was performed on a series of supported Pt/AlF 3 catalysts. These catalysts are very active and stable in the reaction, and the 0.2Pt/AlF 3 catalyst gives the highest specific reaction rate of 207.3 μmol g Pt −1 s −1 at 220 °C. The 1Pt/AlF 3 is much more active than the reference Pt/Al 2 O 3 catalyst, due to its higher content of metallic Pt species than that in the Pt/Al 2 O 3 . Furthermore, turnover frequency (TOF) based on Pt dispersion increases with the surface concentration of metallic Pt 0 in the catalyst, suggesting these species might be the active sites. Furthermore, synergistic roles of metallic and oxidized Pt species are found, as the TOFs calculated based on surface Pt 0 concentration reaches a maximum at the Pt 0 /Pt 2+ molar ratio of about 1. Such optimal Pt 0 /Pt 2+ ratio implies the requirement of Pt 0 Pt 2+ pair in the reaction, probably due to the activation and cleavage of C H bond on metallic Pt atom and the sequential oxidation on the oxidized Pt atoms.
研究领域:
催化化学
·
环境化学
·
材料化学
·
表面科学
·
能源化学
✓ 已验证
DOI
高影响因子
COMBUSTION AND FLAME
·
2019
·
IF 4.12
Jun Wang,Yanyang Qu,Feiyan Gong,Jinpeng Shen,Long Zhang
Aluminum based energetic nanomaterials attract significant attention for various applications owing to their ultrahigh energy density . The main obstacle in the application of nano-Al based energetic materials is the slow combustion reaction kinetics and reduced energy output resulting from the inert Al 2 O 3 shell. In this paper, an efficient surface self-activation strategy is proposed to significantly improve the combustion performance and energy output of nano-Al based energetic materials. A porous AlF 3 shell is formed on the surface of the nano-Al particle by an etching reaction between perfluorododecanoic acid and the Al 2 O 3 dense layer. The porous AlF 3 shell provides a new reaction channel for the reaction of Al and the oxidizer , thus significantly improving the energy output and combustion reaction kinetics. The energy output and combustion reaction speed of polytetrafluoroethylene (PTFE)/nano-Al coated with C 11 F 23 COOH are 6304 J/g and 670 m/s, which are 3.0 and 2.6 times higher than those of PTFE/nano-Al, respectively. The mechanism of the self-activating process is proposed to explain the enhanced combustion reaction kinetics and energy output of the nano-Al based energetic materials. The proposed surface self-activation strategy for nano-Al particles can efficiently to enhance the reactivity and energy output and promote the development of the nano-Al based energetic materials.
研究领域:
材料科学
·
化学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2022
·Vol. 16
·期 6
·8269-8280
·
IF 10.269
Wu Hao,Song Ziyu,Wang Xingxing,Feng Wenfang,Zhou Zhibin,Zhang Heng
Effective passivation of aluminum (Al) current collector at high potentials (> 4.0 V vs. Li/Li + ) is of essence for the long-term operation of lithium-based batteries. Unfortunately, the non-aqueous liquid electrolytes comprising lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and organic carbonates are corrosive toward Al current collector at high potentials (> 4.0 V vs. Li/Li + ), despite their intriguing features (e.g., good chemical stability and high ionic conductivity). Herein, we propose the utilization of N,N-dimethyl fluorosulfonamide (DMFSA) as electrolyte solvent for suppressing Al corrosion in the LiTFSI-based electrolytes. It has been demonstrated that the electrolyte of 1.0 M LiTFSI-DMFSA shows decent ionic conductivities (1.76 mS·cm −1 at 25 °C) with good fluidities (2.44 cP at 25 °C). In particular, the replacement of organic carbonates (e.g., ethylene carbonate and ethyl methyl carbonate) with DMFSA leads to significant suppressed Al corrosion. Morphological and compositional characterizations utilizing scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) reveal that DMFSA favors the formation of insoluble species (i.e., aluminum fluoride (AlF 3 )) on the surface of Al electrode, which effectively inhibits continuous exposure of fresh Al surface to electrolyte during cycling. This work provides not only a deeper understanding on the Al corrosion in LiTFSI-based electrolyte but also an elegant path to stabilize the Al current collector at high potentials (> 4.0 V vs. Li/Li + ), which may give an impetus into the development of lithium-based batteries.
研究领域:
电化学
·
材料科学
·
储能技术
·
腐蚀科学
·
电池技术
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·Vol. 35
·期 48
·2507563
·
IF 19
Ke Su,Lefu Mei,Zunqi Liu,Xin Pan,Pengfei Shuai,Jiyang Xie,Bin Ma,Qingfeng Guo,Cunjian Lin,Mingxing Chen,Zhijian Peng,Libing Liao,Wanbiao Hu,Guocheng Lv
Balancing sensitivity and detection range in dynamic pressure monitoring materials remains challenging, with commercial ruby (Al 2 O 3 :Cr 3+ ) sensors limited by strong crystal fields, restricting performance under extreme conditions. Here, an innovative strategy utilizing an ordered-to-disordered structural conversion in Cr 3+ doped Ca(Mg,Sc)(Al,Si)O 6 phosphors is introduced. This approach achieves a remarkable blueshift sensitivity of 15.08 nm GPa −1 –2.8 times higher than ordered structures and 41 times higher than commercial sensors while maintaining a broad detection range up to 7.5 GPa. Moreover, enhanced structural rigidity notably improves luminescence intensity and thermal stability. The findings establish a robust paradigm for designing high-performance optical pressure sensors, significantly addressing the traditional trade-off between sensitivity and detection range, showing promising applications in geological exploration and aerospace fields.
研究领域:
材料科学
·
光学传感器
·
高压物理
·
发光材料
✓ 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）