Catalysts
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2019
·Vol. 9
·期 7
·606
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IF 3.444
Chuanmin Ding,Junwen Wang,Yufeng Li,Qian Ma,Lichao Ma,Jing Guo,Zili Ma,Ping Liu,Kan Zhang
The supporting modes of active metal over mesoporous materials play an important role in catalytic performance. The location of Ni nanoparticles inside or outside the mesoporous channel of MCM-41 has a significant influence on the reactivity in partial oxidation of methane to syngas reaction. The characterization data using different techniques (Transmission Electron Microscope (TEM), X-Ray Diffraction (XRD), N2adsorption-desorption, H2Temperature-Programmed Reduction (H2-TPR), and Inductively Coupled Plasma (ICP)) indicated that nickel was located outside the mesoporous channels for the impregnation method (Ni/MCM-41), while nickel was encapsulated within MCM-41 via the one-step hydrothermal crystallization method (Ni-MCM-41). The nickel atoms were mainly dispersed predominantly inside the skeleton of zeolite. When the load amount of Ni increased, both of Ni species inside the skeleton or pore channel of zeolite increased, and the ordered structure of MCM-41 was destroyed gradually. Contributed by the strong interaction with MCM-41, the Ni particles of Ni-MCM-41 were highly dispersed with smaller particle size compared with supported Ni/MCM-41 catalyst. The Ni-MCM-41 displayed higher catalytic performance than Ni/MCM-41, especially 10% Ni-MCM-41 due to high dispersity of Ni. The confinement effect of MCM-41 zeolite also afforded high resistance of sintering and coking for 10% Ni-MCM-41 catalyst. Especially, 10% Ni-MCM-41 catalyst showed outstanding catalytic stability.Keywords:partial oxidation of methane;sintering and coking resistance;Ni location;confinement effect;MCM-41 zeolite
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2022
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IF 24.319
Zihao Cui,Peng Wang,Yaqiang Wu,Xiaolei Liu,Guoqiang Chen,Peng Gao,Qianqian Zhang,Zeyan Wang,Zhaoke Zheng,Hefeng Cheng,Yuanyuan Liu,Ying Dai,Baibiao Huang
A facile and effective impregnation method is employed to synthesize the space-confined growth of lead-free halide perovskite Cs 3 Bi 2 Br 9 in MCM-41 molecular sieve. This MCM-41 @CBB (Cs 3 Bi 2 Br 9 ) composite shows an outstanding performance for the photocatalytic reduction of CO 2 to CO at the gas−solid condition under visible-light irradiation. The CO production rate of the MCM-41 @ 50 wt% CBB is determined to be 17.24 μmol g −1 h −1 , which greatly exceeds that of pure CBB (1.89 μmol g −1 h −1 ). The composite is highly stable showing no apparent decrease in the catalytic activity after 8 cycles of repeated experiment. The performance of space-confined growth of CBB nanoparticles in the serial molecular sieve exhibits 2.97–13.4 fold higher than that of pure CBB, respectively, which is superb than CPB (CsPbBr 3 ) and MCM-41 @CPB prepared in the same condition. The results are comparable with those reported for many lead halide perovskites, and are in the top among the lead-free perovskites, especially bismuth halide perovskites.
研究领域:
材料科学
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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
Journal of Renewable and Sustainable Energy
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2016
·Vol. 8
·期 5
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IF 0.961
Lu Meizhen,Liu Xuejun,Li Yongqiang,Nie Yong,Lu Xianghong,Deng Dongshun,Xie Qinglong,Ji Jianbing
Bi-functional catalysts consisting of platinum on aluminosilicate MCM-41 materials with Si/Al ratios between 10 and 30 were prepared via direct mixed-gel synthesis. The catalysts were tested in the hydrocracking of bio-alkanes, produced from biodiesel hydrodeoxygenation and composed of n-hexadecane and n-octadecane, for the production of bio-jet fuel. The effects of temperature, pressure, weight hourly space velocity (WHSV), and H 2 /n-paraffin weight ratio on bio-alkanes conversion and product distribution were examined. The conversion was found to be dependent on the acid strength of the catalyst supports which were proportional to the Al content. However, the catalyst selectivity decreased with the increasing Al content. The optimal Si/Al ratio, temperature, pressure, WHSV, and H 2 /n-paraffin weight ratio were determined to be 20, 330 °C, 2 MPa, 1 h −1 , and 0.20, respectively. Under these conditions, the bio-alkanes conversion and kerosene/gasoline ratio in the product reached 65.62% and 1.96, respectively.
研究领域:
能源化学
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催化材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
·
IF 13.2
Xue-Yao Pang,Fan-Xiang Meng,Cheng Ma,Si-Yang Ni,Zi-Han Jia,Bo Li,Yu-Xiang Liu,Wei-Wei Gao
Gram-positive bacteria can cause a variety of infectious diseases. Selectively inhibiting Gram-positive bacteria will avoid the misuse of broad-spectrum antibiotics, achieve precise treatment, and delay the development of antibiotic resistance. In this work, we successfully developed an MCM-41 molecular sieve-supported copper-based nanozyme composites (MCM-41-Cu 2 O) for selectively combating Gram-positive bacteria. MCM-41, with its porous structure and excellent biocompatibility, not only serves as a carrier but also neutralizes the positive charges of the metal nanozyme, endowing MCM-41-Cu 2 O with negative zeta potentials. This allows it to interact electrostatically with Gram-positive bacteria, facilitating the penetration of free radicals into the bacterial cell membrane, thereby killing the bacteria. MCM-41-Cu 2 O continuously generates endogenous H 2 O 2 through its glutathione oxidase (GSHOx)-like activity·H 2 O 2 serves as the substrate for peroxidase (POD)-like catalytic reactions, producing •OH radicals, thereby enabling a self-cascade reaction. This approach avoids the toxic side effects associated with excessive exogenous H 2 O 2 and offers higher biosafety with potential for antibacterial applications. DFT calculations reveal that compared to Cu 2 O, MCM-41-Cu 2 O exhibits greater adsorption and decomposition capacity for H 2 O 2 , accelerating reaction rates and enhancing POD-like activity. MCM-41-Cu 2 O selectively targets Gram-positive bacteria, achieving a bactericidal rate of up to 99.6% against S. aureus and B. subtilis while leaving E. coli and P. aeruginosa colonies largely unaffected. Reactive oxygen species (ROS) generated by MCM-41-Cu 2 O-5% disrupt bacterial membranes, leading to depolarization, protein leakage, and bacterial death. Additionally, the MCM-41-Cu 2 O nanocomposites exhibit excellent biocompatibility and demonstrate superior in vivo antibacterial efficacy compared to antibiotics, effectively treating wound infections caused by S. aureus . These findings position MCM-41-Cu 2 O as a promising alternative for treating infections caused by Gram-positive bacteria and provide new insights into the antimicrobial applications of molecular sieves.
研究领域:
生物材料学
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抗菌研究
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纳米医学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
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2024
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IF 3.9
Zhan-Jun Zhu,Zhen-Hong He,Sen-Wang Wang,Bao-Ting Wu,Yue Tian,Yong-Chang Sun,Kuan Wang,Weitao Wang,Huan Wang,Zhao-Tie Liu
Compared with conventional thermal catalysis reaction, the photothermal CO 2 -assisted oxidative dehydrogenation of propane (CO 2 -ODHP) to produce propylene and CO is an environmentally friendly and sustainable method that operates at lower temperatures. In the present work, we have developed a series of Co-Mn/MCM-41 catalysts and utilized them in the photothermal CO 2 -ODHP reaction. Among these catalysts, the sample with Co and Mn loadings of 3 % resulted in activities of 225.7 μmol g cat −1 h −1 of propylene and 272.0 μmol g cat −1 h −1 of CO at 250 °C. Characterization results revealed that the electron transfer and interplay between Co and Mn oxides enhance the photoelectronic response and reduce impedance, facilitating the electron transfer process. Besides, the Co and Mn bimetallic species could enhance photothermal conversion efficiency and further enhance the local temperature during the reaction. The present work introduces a novel strategy for building supported bimetallic oxides in achieving CO 2 -ODHP via the photothermal route and is also expected to provide an optional catalyst required satisfactions including efficient electron transfer and photothermal conversion for other photothermal reactions.
研究领域:
催化化学
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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 LUMINESCENCE
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2022
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IF 4.171
Zhaoping Chen,Qin Wang,Ziyao He,Jiaming Li,Enrou Mei,Xiaojuan Liang,Weidong Xiang
CsPbX 3 (X = Cl, Br, I) perovskites have emerged as promising candidate lasing materials due to their high optical gain , low defect state density, and high absorption coefficient. Unfortunately, they suffer from poor stability, particularly with respect to temperature, moisture, and light exposure, preventing their use in practical optoelectronic applications , such as for amplified spontaneous emission (ASE) with an ultralow laser threshold. Herein, CsPbBr 3 @MCM-41 molecular sieve (CMM) composites are controllably prepared by different ultrasonication and stirring treatments. In addition, different perovskite concentrations and heat-treatment conditions are also considered to demonstrate the ASE behaviors. In addition, CMM@PS (CMMP) and CMM@AB (CMMA) composites were fabricated successfully by further optimizing the mixing ratio of CMM and the polymer. More excitingly, the stability of the CMM@polymer films with respect to the external environment is greatly improved after the polymer coating . To our surprise, the CMM@ploymer thin films demonstrated ASE at room-temperature, with an ASE threshold as low as 0.136 mJ/cm 2 and 0.049 mJ/cm 2 for CMMA and CMMP, respectively. These results clearly shed light upon the control and optimization of CsPbBr 3 perovskite composite films , paving the way for their widespread use in optoelectronic applications .
研究领域:
光学材料
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纳米复合材料
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光电子学
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激光物理
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功能薄膜
✓ 已验证
DOI
高影响因子
MEASUREMENT SCIENCE and TECHNOLOGY
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2024
·Vol. 35
·期 9
·095205
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IF 2.7
Feng Gu,Chunhua Wei,Lingrui Jiao,Yingzheng Liu,Di Peng
Motion- and temperature-induced errors are the major sources of error in pressure-sensitive paint (PSP) measurement. In this study, we developed a novel dual-luminophore fast-responding PSP with reference and pressure-sensitive channels that have similar temperature sensitivities, enabling motion- and temperature-induced errors to be simultaneously eliminated by taking the intensity ratio of the two channels. Rhodamine B (RhB), which was loaded on the Mobil Composition of Matter No. 41 (MCM-41) molecular sieve, and platinum tetrakis (pentafluorophenyl) porphyrin (PtTFPP) were chosen as the reference and pressure-sensitive luminophores, respectively. These luminophores were mixed with mesoporous SiO2 particles and a small amount of polymer to form a sprayable motion–temperature cancellation (MTC) PSP. By controlling the concentration of RhB, the temperature sensitivity of the reference channel was adjusted to match that of PtTFPP. To minimize temperature-induced errors, the effect of spectral ranges was also investigated. The lowest temperature sensitivity achieved for the MTC-PSP was 0.025%/°C, yielding an extremely low temperature-induced error of 55 Pa °C−1. Its pressure sensitivity and response time were 0.46%/kPa and 145 μs, respectively. In addition, a theoretical model for the MTC-PSP that considers the effect of spectral overlap was proposed. The model accurately predicted the nonlinear relationship between the intensity ratio and pressure. The capability of the MTC-PSP was confirmed in a fast-rotating-disk experiment, and the pressure results agreed well with the theoretical pressure distribution on the disk.
CAS / MDL:
研究领域:
物理学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
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