CHEMICAL PHYSICS LETTERS
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2024
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IF 2.8
Aihu Feng,Jieyan Dai,Xu Gao,Yun Yu
Surfactant-templating strategy is an effective method to construct the hierarchical zeolite with controllable mesopores. In this work, the hierarchical NaY zeolites with the mesoporous size of ∼ 2.6 nm and ∼ 3.5 nm are obtained via the chemical etching and surfactant-templating process, and the formation mechanism of mesopores with controllable pore size is elucidated. The saturated adsorption capacity of toluene for H 2 C 2 O 4 -etched NaY-C10 and NH 4 HF 2 -etched NaY-C16 is 208 mg·g −1 and 215 mg·g −1 , respectively. A new type of hierarchical NaY zeolite with excellent toluene adsorption properties is developed.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
CARBON
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2016
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IF 6.198
Aibing Chen,Yuetong Li,Yifeng Yu,Yunqian Li,Kechan Xia,Yuying Wang,Shuhui Li,Linsong Zhang
A synthetic procedure to prepare hollow mesoporous carbon spheres (HMCSs) with uniform mesopore size on the shell was developed using the “dissolution-capture” method. The dissolution-capture process was performed in the polystyrene core and silica shell. The polystyrene core template was dissolved by tetrahydrofuran treatment to form a hollow cavity. Then, the polystyrene was entrapped into the mesochannel of the silica shell. After carbonization and etching of silica, HMCSs with uniform mesopore size (4.1 nm) were produced. The HMCSs exhibit a greater capacity for phenol adsorption and reuse, thus making them ideal adsorbents for phenol adsorption.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
MICROCHIMICA ACTA
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2019
·Vol. 186
·期 2
·1-8
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IF 5.479
Xia Hongjun,Wang Jun,Chen Gang,Liu Jiawei,Wan Guangpin,Bai Quan
Monodisperse SiO 2 @SiO 2 core-shell silica microspheres (CSSM) with enlarged mesopores perpendicular to the particles surface were prepared using a dual-templating approach. With cetyltrimethyl ammonium bromide as the template and octyltrimethyl ammonium bromide as an auxiliary chemical, the pore size can be enlarged from 2.6 to 10.6 nm. The average shell thickness can be increased from 31 nm to 97 nm by adjusting the concentrations of the surfactants under continuous addition of tetraethyl orthosilicate. After coating twice, the resulting CSSM has a uniform mesoporous shell of about 198 nm thickness and a narrow pore size distribution. The CSSM were then modified with octadecyltrichlorosilane to give a material referred to as CS-C18. It was evaluated by separating the mixture of methylbenzene (toluene), ethylbenzene, n-propylbenzene, n-butylbenzene, n-amylbenzene and hexylbenzene. The baseline separation of the six alkyl benzenes is achieved within 2 min. Compared to a commercial column of type BEH-C18, CS-C18 shows a faster and better separation even at lower back pressure. It was also applied to the fast separation of benzo[a]pyrene, salbutamol, ractopamine and clenbuterolin residues in pork samples. The high column efficiency and better reproducibility suggest that the CSSM can be used as a matrix for fast separation and analysis of several kinds of small analytes.
A dual-templating approach was utilized to produce the core shell microsphere with controllable mesopore channels by using hexadecyltrimethylammonium bromide (CTAB) as the template and trioctylmethylammonium bromide (TOMAB) as an auxiliary chemical to enlarge the size of CTAB micelles.
研究领域:
材料科学
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分析化学
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DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2019
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IF 3.218
Yunshu Zhang,Dandan Wang,Xiaolin Wang,Fuming Chen
The electro-synthesis of hydrogen peroxide (H 2 O 2 ) through the two-electron oxygen reduction reaction (ORR) is an inexpensive and environmentally friendly process. In this study, as catalysts for the ORR, two kinds of activated carbon (AC) with different mesopore size distributions are modified by nitrogen (N)-doping and cobalt oxide (CoO x )-loading treatment. It can be concluded that pyridinic-N and pyrrolic-N (48.94%) are more easily formed on the AC with narrow mesopore size distributions (AC-1, 2–5 nm), however, graphite-N (63.9%) are more easily formed on the AC with broad mesopore size distributions (AC-2, 5–15 nm). Furthermore, Co 3 O 4 and CoO is the predominant crystal loaded onto the modified AC-1 and modified AC-2, respectively. The modified AC-1 has an extremely high propensity for a four-electron ORR pathway, while the modified AC-2 has an extremely high propensity for a two-electron ORR pathway. In addition, a rolling activated carbon electrode (RACE) with low-cost and high-efficiency is fabricated by modified AC-2. The H 2 O 2 electro-synthesis rate and current efficiency for the RACE are 0.236 ± 0.025 mg/h/mA/cm 2 and 63.25 ± 6.79%, respectively.
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
MICROPOROUS AND MESOPOROUS MATERIALS
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2016
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IF 3.349
Lijun Xue,Di Zhang,Yongqiang Xu,Xinmei Liu
γ-Al 2 O 3 without amorphous domains was synthesized by cation-anion double hydrolysis method. The mesopore size in the range of 3.9–8.5 nm was easily controlled by regulating crystallization temperature, solution pH value and the concentration of NaAlO 2 . The introduction of MoO 3 to the γ-Al 2 O 3 via impregnation method can lead to a decrease of specific surface areas, pore sizes and pore volumes of the supports. The less steric hindrance of the larger mesopores (particularly 8.5 nm) exhibits the more Lewis acid sites over the γ-Al 2 O 3 . The MoO 3 /γ-Al 2 O 3 possesses more Bronsted acid sites compared to Lewis. The thiophene compounds can be adsorbed both on the supports and catalysts. The acid sites can facilitate the interaction between the thiophene compounds and catalysts (or supports). The more adsorbed thiophene and dibenzothiophene on the catalysts is attributed to the coordinately unsaturated metal sites and Bronsted acid sites on the surface of the catalysts. Of note is the supports and catalysts with larger pore size (especially 8.5 nm) could promote the adsorption of thiophene compounds. It demonstrates that there is pore confinement effect in the hydrodesulfurization catalysts.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
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IF 8.1
Changxu Li,Beibei Yan,Dahai Pan,Feng Yu,Xiaoliang Yan,Shuwei Chen,Binbin Fan,Ruifeng Li
Mesoporous alumina (MA) materials with outstanding textural properties have been synthesized by a facile approach, and were evaluated as supports of Pt-based catalyst for methylcyclohexane dehydrogenation . At 300 °C, the resultant catalyst demonstrates a much higher activity with a maximum hydrogen evolution rate of 2081 mmol/g Pt /min in comparison with the state-of-the-art alumina supported Pt catalysts. Interestingly, even after a long-time reaction of 100 h or regeneration, more than 80% of original activity was still maintained. The superior catalytic performance of the obtained catalyst is associated with the high specific surface area and large mesoporous size of support MA, thus benefiting the increase in the number of Pt active sites and efficiently inhibiting the formation of coke deposition during the reaction. Our contribution has provided a rational design strategy for highly efficient and stable dehydrogenation catalysts, which is a key for the utilization of methylcyclohexane-toluene system in hydrogen storage technology.
研究领域:
催化
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材料科学
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化学工程
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能源存储
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DOI
高影响因子
ANALYTICAL LETTERS
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2022
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IF 2.267
Yu Huang,Yi Wu,Wenhui Li,Xiaohui Yan,Dapeng Wu
Highly spherical porous silica particles (PSPs) with a controlled pore size were prepared by ultrasonic spray drying and were used as a packing material for high-performance liquid chromatography (HPLC). By using organic additives added to the silica sol as porogens instead of low-melting salts, choosing the size of the colloidal SiO2 particles, and varying the type and the ratio of additives, the pore size of the PSPs was finely tuned from 2.9 to 34.4 nm. Subsequently, PSPs having pore sizes of 7.4, 13.5, and 29.0 nm were modified by chlorodimethyloctadecylsilane (PSPs-C18), and HPLC columns packed with the different PSPs-C18 were evaluated systematically using aromatic compounds and alkylbenzene derivatives as probes. A plate number of 81,000/m and the relative standard deviation of less than 1% in the retention time were obtained for pentylbenzene over 100 injection and HPLC separation cycles for the 7.4-PSPs-C18 column. Five proteins were also separated within 25 min using the 29.0-PSPs-C18 column.
研究领域:
材料科学
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分析化学
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化工工程
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高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
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2020
·Vol. 94
·期 2
·416-424
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IF 2.008
Tian Wei,Du Bin,Shui Anze,Ke Shanjun,Shan Qingliang,He Chao,Ma Juan
In this work, a silica-based mesoporous oxide (SMO) was directly fabricated via a template-free method using the abundant and inexpensive volcanic ash as raw material. By alkali hydrothermal activation and acid hydrothermal etching of volcanic ash, the SMO with large mesopore size (7.94 nm), high specific surface area (459.5 m 2 /g), and total pore volume of 1.05 cm 3 /g was produced. The main ingredient of SMO is amorphous microporous silica. The structural evolutions of the mesoporous materials were revealed by X-ray powder diffraction, scanning electron microscope, Fourier transform infrared spectrometry, N 2 adsorption/desorption, and transmission electron microscopy techniques. The as-prepared SMO possessed excellent adsorption of water vapor as high as 616.0 g/m 2 at the relative humidity ranging from 33 to 75%. This SMO provides a platform for preparing high performance template-freely humidity self-regulating material.
This figure shows that silica-based mesoporous oxide (SMO) quickly adsorbs moisture at RH = 75% and reaches to 616.0 g/m 2 , and then the adsorbed water releases at 33% RH. These results suggest SMO have an excellent humidity self-regulating function in the RH ranging from 33 to 75%.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
CATALYSIS LETTERS
·
2023
·
IF 2.8
Hao Runming,Du An,Zhu Qingling,Wu Xue,Liu Sijia,Wang Ke,Wang Yang
5-Hydroxymethylfurfural (HMF) is a high value-added platform compound, converted into bio-based polyesters and biofuels etc. In this paper, we used two commercially available hexamethylenimine and cetyltrimethylammonium bromide (CTAB) as the structure-directing agents to synthesize HMWW zeolite nanosheets via one step. A series of HMWW zeolite nanosheets with different disorder index ( DI ) were controllably prepared by adjusting the amount of CTAB, operating also as an in situ exfoliating agent, converting fructose into HMF in the tetrahydrofuran/NaCl-H 2 O biphasic solvent with low boiling point. Successful construction of disordered HMWW zeolite nanosheets was verified by PXRD. Further characterizations by BET, SEM and TEM etc. show that HMWW 4.0 with the optimum DI of 0.67 has a disordered network-like arrangement of layers with the external surface area of 224 m 2 /g and the mesoporous size of 3.5 nm. Catalytic evaluations showed that HMF selectivity was closely related to DI of the catalysts. Under the optimized DI , fructose molecules are readily accessible to acidic sites on the external surface while larger external surface area is exposed. The HMWW 4.0 zeolite catalyzed fructose dehydration in the biphasic solvent, producing 90% HMF selectivity with 93% fructose conversion at 140 °C for 6 h. In the reuses of the HMWW 4.0 catalyst, HMF selectivity was around 90% with fructose conversion decreasing by ca. 10% after six runs, indicating that it possesses the promising stability. Graphical Abstract
研究领域:
化学
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材料科学
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催化
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纳米技术
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生物化学
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高影响因子
危险品化学品经营许可证（带存储）