JOURNAL OF ALLOYS AND COMPOUNDS
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2024
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IF 5.8
Kai Su,Xuekun Tian,Xinmei Hou,Zhenyi Zhao,Xusheng Liu,Deze Ouyang,Huiyu Yuan,Xinhong Liu
Ti 3 AlC 2 powder was prepared via an efficient solid-liquid reaction in flowing argon using coconut shell charcoal as novel carbon source, and phase evolution, microstructure and oxidation behavior of Ti 3 AlC 2 powder were investigated. The results show that coconut shell charcoal is dominated by amorphous carbon after carbonization with some turbostratic graphite-like structure, and large specific surface area of coconut shell charcoal gives its excellent reactivity. Ti 3 AlC 2 powder prepared at 1400 °C for 1.5 h exhibits good crystallinity and typical nanolayered structure. Ti 3 AlC 2 powder remains thermally stable in air below 552 °C, while oxidizing occurs rapidly between 900 and 1100 °C. The isothermal oxidation curves show a parabolic-like, indicating that the oxidation process is primarily controlled by a diffusion mechanism. The good oxidation resistance of Ti 3 AlC 2 powder is attributed to the oxidized products of TiO 2 and Al 2 O 3 grains formed a connected and dense protective layer on the particle surface at elevated temperatures.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Xueye Wang,Jinxing Ma,Zhiwei Wang,Haiqin Chen,Mingxian Liu,Zhichao Wu
Sodium hypochlorite (NaOCl) is a widely used cleaning reagent for membrane separation processes to recover membrane permeability; however, the competitive interactions of different chlorine species with fouling layers have not been adequately elucidated. In this work, we investigated the pH-dependent diffusion of the active chlorine species and reactions involved in the consequent dissociation and/or destruction of the fouling layers. The hypochlorite conductivity and dynamic diffusion tests showed that an increase in pH facilitated the uneven and fast diffusion of active chlorine via relaxing the matrix structure of the fouling layer. Under the synergetic effects of oxidation , hydrolysis and hydraulic shearing, the enhanced diffusion resulted in an uneven but massive removal of the foulants rather than a layer-by-layer dissociation, leading to a higher membrane cleaning efficiency. Sodium dodecyl sulfate (SDS), an anionic surfactant , was added into the cleaning solution to further validate the diffusion-dependent cleaning mechanisms. With a faster diffusion process aided by SDS, the cleaning efficiency was significantly improved. These findings provide new insight into the chemical cleaning mechanisms, which are of great importance to the optimisation of cleaning efficiency for various membrane-based processes.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ChemNanoMat
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2019
·Vol. 5
·期 9
·1244-1250
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IF 3.431
Yuxiu Sun,Hongliang Huang,Xiangyu Guo,Zhihua Qiao,Chongli Zhong
Graphical Counter diffusion has been used to drive the in situ formation of mixed metal MOF membranes in a confined space with nanostructure arrays under hydrothermal conditions. Through this approach, a variety of mixed metal ZIF membranes can be synthesized on different kinds of porous substrates. The development of facile, versatile strategies for the fabrication of mixed component metal-organic framework (MOF) membranes is highly desired, but still very challenging due to the difficulty in controlling crystal growth rates of every single component in a specific confined space. It is difficult to adjust the formation of multicomponent MOF membrane in a controlled manner using conventional approaches such as secondary growth methods. Herein, we present a facile strategy that prepares the mixed metal zeolitic imidazolate framework (ZIF) membranes in situ in a confined space with nanostructure arrays under hydrothermal conditions using the counter diffusion mechanism. The counter diffusion of different metal ions from both the homogeneous bulk solution and the solid metal oxide nanostructure grown on substrate leads to the specific effective reaction zone by encountering with linker molecules at the interface. Subsequently, nucleation and crystal growth generate the continuous mixed metal MOF membranes. With this approach, a variety of mixed metal ZIF membranes were synthesized on different kinds of substrates. The prepared membranes exhibited good sieving effect to H 2 and heavier gas molecules during both single and mixed gas permeation tests. This work opens a fresh avenue for the synthesis of mixed component MOF membranes, and the counter diffusion effect can be intentionally adopted to the design and fabrication of selective mixed metal MOF membrane on various supports.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2014
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IF 2.726
Zhixiao Zhang,Chongjun Xu,Xianwu Du,Zili Li,Jilin Wang,Weihong Xing,Yuan Sheng,Weimin Wang,Zhengyi Fu
High-performance TiB 2 –SiC composites were fabricated with a new reaction system of B 4 C–TiC–Si by reactive hot pressing. The reaction process was controlled by the diffusion of boron atoms and hindered by the accumulated product layer of TiB 2 and C. The melting Si can offer another diffusion path for boron atoms, thereby promoting the reaction process. The Vickers hardness , flexural strength , and fracture toughness of the fabricated TiB 2 –SiC composites respectively reached 28.6 ± 0.6 GPa, 654 ± 49 MPa, and 6.8 ± 0.5 MPa m 1/2 . Both the intergranular fracture resulting from mismatch in thermal expansion coefficient between TiB 2 and SiC and the transgranular fracture resulting from the network structure of TiB 2 can enhance the fracture toughness of the TiB 2 –SiC composite.
研究领域:
材料科学
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机械工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Qing Wang,Yu Guo,Nong Xu,Qiao Liu,Bin Wang,Long Fan,Lingyun Zhang,Rongfei Zhou
Membrane-based pervaporation (PV) is an energy-efficient separation technology for liquid molecular mixtures, which is an increasingly important function in chemical industries. This work accomplished the first synthesis of high-performance FAU (NaX type) zeolite membranes on α-alumina tubular supports via the secondary growth method using 50 nm nanoseeds. The effects that the synthesis parameters exerted on the crystal structures, morphologies, and PV performance of FAU membranes were systematically investigated. The nanosized seeds showed high levels of activity that promoted the rapid growth of the zeolite layer. In addition, either extending the crystallization time or raising the temperature readily caused trans -crystallization to form NaP impurity zeolites, which decreased the membrane flux and separation factor. When synthesis conditions were optimized, a high-quality and pure-phase FAU membrane was obtained and tested for the permeation of single gases and for the PV dehydration of various organic solvents (methanol, ethanol, n-propanol, iso-propanol, and tert-butanol). The relationships between the single-gas permeance, PV permeance, and polarity index were investigated using a similar size range of permeate molecules (0.289–0.5061 nm). The results show that gas permeance exhibits Knudsen selectivity. The PV permeance, however, correlated well with the polarity index of the permeate, which indicates that PV dehydration through the FAU membrane is controlled by an adsorption-diffusion mechanism. Moreover, the correlation provides a new tool for predicting PV performance. Compared with studies using FAU membranes, the as-synthesized FAU membrane features good reproducibility, excellent stability, and high PV performance, which suggests the great potential of FAU membranes for use in industrial organic solvent dehydration.
研究领域:
化学工程
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
·
IF 8.4
Zhifei Hu,Zejiao Wang,Mingming Wang,Zhigang Wang,Yuanyuan Chu,Xiaoyao Tan,Yunxia Hu,Tianjia Chen,Shaomin Liu
Dense metal membranes are widely studied due to their promising performance in hydrogen separation. In this work, the low-cost dense iron (Fe) hollow fiber membranes (FeHFMs) were developed via the phase inversion and high-temperature sintering method. By tuning the preparation conditions, two typical gas-tight hollow fibers referred to as the sandwich- and honeycomb-structured membranes were successfully synthesized. H 2 permeation behavior was well described by Sieverts equation based on the solution-diffusion mechanism. The sandwich-structured FeHFMs had an H 2 flux of up to 7.51 mmol m −2 s −1 when operated at a temperature of 850 °C. In comparison, the honeycomb-structured FeHFMs further enhanced the H 2 flux by a factor of 3.2 due to the optimized membrane morphology with only one single dense iron layer. The developed FeHFMs showed superior H 2 permeation stability in thermal shock tests (40 h) and long-term stability tests (120 h). This work also expanded the potential application horizons of the FeHFMs, which can be easily tailored into porous or dense structures by tuning the sintering conditions.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2025
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IF 19
Rui Wang,Rong Zhang,Yixin Yan,Gaoyang Li,Yuan Li,Fujuan Wang,Youzhi Wu,Fen Ran
Co 3 V 2 O 8 as a bimetallic oxide with “fast-charging” capacity presents some potential advantages, comprising decent theoretical specific capacity, favorable crystal structure, and intrinsic safety. Presently, although extensive research of Co 3 V 2 O 8 as an anode material are reported, the formed Co° from Co 3 V 2 O 8 after the initial discharging is not oxidized to CoO during the charging process, and the ion diffusion mechanism are not well clarified. The lithium-storage process of Co 3 V 2 O 8 and the diffusion mechanism of lithium ion in Co 3 V 2 O 8 are studied in detail in this work. A hollow-micropencil Co 3 V 2 O 8 prepared through the hydrothermal method without using surfactants or templates demonstrates a high “fast-charging” capability even at the current densities as high as 1.0–2.0 A g −1 . The electrochemical kinetic results illustrate that the hollow-micropencil Co 3 V 2 O 8 presents low charge transfer resistance. The distinctive lithium ion storage sites as well as diffusion paths are predicted. The in situ X-ray diffraction analysis is adopted to confirm that the formed Co° after the initial discharging is not oxidized to CoO during the delithiation process. The work not only helps to understand the lithium insertion mechanisms of Co 3 V 2 O 8 but also offers new means to develop “fast-charging” anode material for lithium-ion batteries with remarkable electrochemical performance.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2024
·
IF 4.1
Chengming Guo,Pengtao Guo,Youbin Zhou,Xin Yan,Huifang Li,Dahuan Liu
Porous adsorbents are widely used for the adsorptive separation of carbon dioxide (CO 2 ) from gas mixtures, offering a promising solution to address both the energy crisis and environmental issues. However, developing highly efficient CO 2 selective adsorbents has been challenging due to the similar physicochemical properties of CO 2 and other gases. To overcome this challenge, we herein have developed a core–shell composite utilizing ionic liquids (ILs) and metal–organic frameworks (MOFs) based on the dissolution-diffusion mechanism. The unique solubility differences of ILs for various gas molecules, particularly their strong solubility for CO 2 , allow only CO 2 to be adsorbed while excluding other gases. As a result, the composite exhibits a remarkable separation selectivity for CO 2 /C 2 H 2 , CO 2 /CH 4 and CO 2 /N 2 . Breakthrough experiments have verified the outstanding performance of this core–shell composite in separating gas mixtures containing CO 2 impurities. Remarkably, this composite can be synthesized by a simple method, which is more practical for large-scale production.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Guanhua Liu,Zhongyi Jiang,Hao Yang,Changdong Li,Hongjian Wang,Meidi Wang,Yimeng Song,Hong Wu,Fusheng Pan
Covalent organic framework (COF) is an emergent class of ordered porous materials with high stability. The fabrication of thin and continuous COF membrane for small molecule separation remains challenging due to the relatively large pore size of COF materials and weak COF-substrate interfacial interaction. Herein, a two-dimensional COF layer was spin-coated on a porous substrate followed by constructing a bio-inspired calcium alginate (Alg-Ca) layer to obtain a dual-layer membrane with a thickness less than 100 nm. The Alg-Ca layer afforded a superhydrophilic surface to capture water molecules, and the porous COF layer rendered selective water channels. The dual-layer membrane synergistically strenthened the solution-diffusion mechanism through the manipulation of the membrane structure and transport process. The synergy of two layers endowed the membrane with superior water-selective performance with permeation flux of 3614 g/(m 2 h) and water content in permeate of 99.7 wt% for n -butanol dehydration. The fabrication of dual-layer membrane in this study may offer a new strategy for highly efficient separation of liquid small molecule mixtures.
研究领域:
材料科学
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分离工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
COMBUSTION AND FLAME
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2024
·
IF 5.8
Tianyu Yang,Xiaoyan Qian,Jinyu Dai,Jun Liu,Jiuyu Chen,Jiaxin Wang,Minggao Xu,Yunlan Sun,Baozhong Zhu
Boron (B) powder, with its high mass and volumetric heat values, makes it highly promising in the field of energetic materials. However, the oxide layer on the B surface is the most significant barrier to realizing its full potential as a fuel. How to eliminate or disrupt the oxide layer is currently an urgent problem that needs to be addressed. This study proposes an approach to enhance the combustion of nano-B powder by coating aluminum (Al) onto its surface using a silane coupling agent. The combustion characteristics of Al-modified B powder with different Al contents were investigated through experimental and molecular dynamic simulation methods, and the bidirectional diffusion mechanism on the interfacial layer of modified B particles was revealed. A small amount of Al powder can largely lower the initial oxidation temperature of B powder, increase the maximum flame temperature, and enhance the heat release. However, an excessive amount of Al powder leads to a deterioration in the combustion of B powder but can alter the combustion behavior and suppress the aggregation of B powder during the combustion. Additionally, combination reaction and redox reaction occurring during the combustion of B@Al samples not only reduce the burning time of B powder but also accelerate the flame expansion speed and improve the combustion efficiency . These results lay the foundation for the application of B@Al in the field of energetic materials.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2023
·
IF 9.2
Wenlong Zhang,Huanxin Li,Han Zhou,Xiaohui Ning
Carbonaceous materials that possess reversible anions storage capacity and can worked as the cathode for Ni/NiCl 2 -Graphite battery . However, differences in storage capacity of carbonaceous cathodes and factors affecting anions storage capacity have not been thoroughly investigated. Here, we systematically evaluated the electrochemical properties and intercalation reaction mechanism of carbonaceous materials cathodes firstly. Expanded graphite and graphite paper cathodes display the highest specific capacity of 72 mAh/g and diffusion-controlled capacity ratios (∼98 %). X-ray powder diffraction and Raman spectroscopy analysis on the graphite intermetallic compounds confirmed the presence of stage-5 intercalation/de-intercalation reactions. Density functional theory calculation and ionic diffusion model analysis showed that the intercalation and diffusion process of AlCl 4 - in graphite interlayers play a crucial role in anions storage reaction. Rich-in-edged outer graphite-layers are more conducive to form intercalation reaction active sites and store anions effectively. The expanded graphite electrode exhibits the highest intercalation reaction ratio (φ R-GP = 1.40), confirming sufficient intercalation reaction active sites in each unit mass. And the multiple wrinkles and curled graphite sheets in expanded graphite provide adequate ionic transport/diffusion channels during electrochemical intercalation/de-intercalation reactions. Our findings provide significant support for understanding anions storage behaviors and designing cathodes with high anions storage capacity in the Ni/NiCl 2 -Graphite battery .
研究领域:
电化学
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材料科学
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能源存储
·
电池技术
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固态离子学
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纳米材料
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物理化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Cuizhu Ye,Xingguang Chen,Dong Zhang,Junjun Xu,Huiting Xi,Tiantian Wu,Danwen Deng,Chunhong Xiong,Jinsheng Zhang,Ganhui Huang
Coated with polypyrrole (Ppy)-based molecularly imprinted polymer (MIP), 3D CoFe-metal organic frameworks (CoFe-MOFs) with gold nanoparticles (AuNPs) was developed for electrochemical trace detection of norfloxacin (NOR). On one hand, the trace detection of NOR was realized with MIP/CoFe-MOFs/AuNPs/Glassy carbon electrode (GCE). The effective surface area of the imprinted cavities capable of identifying NOR on MIP/CoFe-MOFs/AuNPs/GCE increased to 0.1058 cm 2 after 3D CoFe-MOFs/AuNPs was modified, which indicates that CoFe-MOFs/AuNPs could generate more imprinted cavities, thus contributing to a lower limit of detection (LOD) of 0.131 pmol L −1 (S/N = 3) with a wider linear range (5–100, 100–1000 and 1000–6000 pmol L −1 ). On the other hand, the recognition reaction to NOR by MIP/CoFe-MOFs/AuNPs/GCE is an irreversible electrochemical oxidation reaction involving an electron and a proton, controlled by a mixed adsorption-diffusion mechanism. Rapid and precise detection of NOR in prescription (norfloxacin capsules with the specification of 0.1 g) and pure milk with the recovery rates between 97.04 and 110.2% and the relative standard deviations (RSD) were less than 5.7%. The measured results by MIP/CoFe-MOFs/AuNPs/GCE were close to the commercial norfloxacin enzyme-linked immunosorbent assay (ELISA) kit, demonstrates its high potential to NOR trace detection in environmental and animal foods.
研究领域:
分析化学
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电化学
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材料科学
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环境科学
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食品科学
✓ 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）