SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Sheng Liu,Yujuan Guo,Shunmin Yi,Shijing Yan,Chaoliu Ouyang,Fei Deng,Chunxue Li,Guangfu Liao,Qing Li
Supported noble metal heterogeneous catalysts have been proven to be effective for the treatment of toxic organic pollutants. Herein, ultrafine Ag nanoparticles (NPs) with an average size of approximately 4.37 nm was decorated on the surface of pure silicon zeolite nanoparticle (PSZN) and confined in pore channels through a low-cost and environmentally friendly in-situ reduction strategy. The prepared Ag/PSZN nanocomposites showed ultrahigh catalytic activity for the reduction of 4-nitrophenol (4-NP) (∼200 s, 17.29 × 10 -3 s −1 ) and methylene blue (MB) (∼4 min, 76.53 × 10 -2 min −1 ), which outperforms the majority of the previously reported Ag-based catalysts. The excellent catalytic performance is due to the large loading amount (W t = 16.8 %) and ultrasmall size of Ag NPs, which provides abundant active sites. Moreover, it showed outstanding recyclability of 93 % and 86 % removal of 4-NP and MB, respectively, after 10 cycle reactions, and stability after 300 days of storage at room temperature. This work offers new insights into the fabrication of Ag-based catalysts for efficiently removing organic pollutants from aqueous solutions.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
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2013
·Vol. 24
·期 6
·600-608
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IF 1.635
Zhenxun Huang,Jianqing Zhao,Yanchao Yuan,Shijing Yan,Shumei Liu,Xingtao Zan
In this study, amino derivative of pure silica zeolite nanocrystal (A-PSZN) was dispersed into polyimide (PI) matrix to prepare PI/A-PSZN hybrid films, and their thermal and mechanical properties, as well as hydrophobicity, were characterized scientifically. The test results show that PI/A-PSZN hybrid films possess higher glass transition temperature, higher thermal stability and lower in-plane coefficient of thermal expansion than pristine PI. The mechanical property data suggest that the incorporation of A-PSZN results in an increase in Young's modulus and tensile strength of the hybrid films, but as its content exceeds the critical value (maybe 5 wt%), its enhancement effect on the hybrid's strength and toughness gets weaker. Furthermore, liquid dripping imaging analysis results indicate that the film's hydrophobicity is clearly improved by the introduction of A-PSZN. As compared with PSZN, A-PSZN exhibits better effect on enhancing the overall performance of pristine PI films. A comparison with other studies suggests that PI/A-PSZN is a hybrid film with superior comprehensive properties. Copyright © 2013 John Wiley & Sons, Ltd.
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 the American Chemical Society
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2023
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IF 15
Chao Ma,Xiaona Liu,Yang Hong,Nana Yan,Chenyang Nie,Jing Wang,Peng Guo,Zhongmin Liu
The pure-silica zeolite plays a crucially important role in the gas separation of alkane/alkene, the low-k dielectric material, and the robust matrix for confining metal species during catalysis. However, the environmentally friendly synthesis of pure-silica zeolites is still challenging since (1) the toxic fluoride or dealuminum seeds are inevitably utilized through the hydrothermal synthesis and (2) it will also take a longer crystallization time. Herein, we present an efficient method called the OSDA-mismatch approach for the fluoride- and seed-free synthesis of pure-silica zeolites using Si-SOD (enriched 4-rings) as the sole silica source. This approach allows for the rapid and green synthesis of 15 pure-silica zeolites (CHA, *BEA, EUO, SFF, STF, -SVR, *-SVY, DOH, MTN, NON, *MRE, MEL, MFI, MTW, and *STO). Furthermore, distinct crystallization mechanisms of two significant pure-silica CHA- and *BEA-type zeolites (denoted as Si-CHA and Si-BEA) are investigated in detail by advanced characterization techniques such as FIB, 3D ED, 4D-STEM, HRTEM, Raman, and 29Si MAS NMR. More importantly, Si-CHA displays promising propane/propylene separation performance even better than the one synthesized in the presence of toxic HF. In addition, the incorporation of Zn species within Si-BEA fabricated by this approach also renders superior performance on propane dehydrogenation.
研究领域:
材料科学
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化学工程
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环境科学
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产品关联
DOI
PubMed
高影响因子
CHEMISTRY OF MATERIALS
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2019
·
IF 10.159
Jiang-Zhen Qiu,Jibo Hu,Jinggang Lan,Long-Fei Wang,Guangying Fu,Rujian Xiao,Binghui Ge,Jiuxing Jiang
As the most active new frontier, a single-atom catalyst (SAC) combining the merits of heterogeneous and homogeneous catalysts would have a significant effect on the 100 year history of ammonia synthesis research. Here, the Ru SAC has been demonstrated to be active and efficient for ammonia synthesis. To this end, an ideal model catalyst, pure siliceous zeolite-supported Ru SAC (Ru SAs/S-1), which shows surprising catalytic ammonia synthesis activity compared to that of a conventional Ru catalyst, was designed. Both atomic-resolution scanning transmission electron microscopy, X-ray absorption spectrometric analysis, and in situ diffuse reflectance infrared Fourier transform spectroscopy identify the single-Ru-atom nature of Ru SAs/S-1 before and after the reaction. Further DFT calculations reveal that the reaction mechanism is different from traditional mechanisms. Therefore, this paper provides an alternative SAC strategy to design high-performance Ru catalysts for ammonia synthesis.
研究领域:
催化化学
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材料科学
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物理化学
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DOI
高影响因子
RSC Advances
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2015
·Vol. 5
·期 93
·76476-76482
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IF 3.84
Zhenxun Huang,Shumei Liu,Yanchao Yuan,Jianqing Zhao
Pure silica zeolite nanocrystal particles functionalized with aminopropyl groups (APSZN) were introduced into a 2,2-bis-(3,4-dicarboxyphenyl)hexafluoropropane dianhydride-2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl polyimide (FPI) matrix to obtain FPI/APSZN hybrid films. The effect of APSZN content on the hybrid films was carefully evaluated in terms of UV-visible transmittance, dielectric constant (κ), coefficient of thermal expansion (CTE), mechanical properties, dynamic mechanical properties and thermal degradation behavior. The κ of the FPI/APSZN hybrid film decreases to 2.56 with 7 wt% APSZN. With increasing content of APSZN the tensile strength and the Young's modulus of FPI/APSZN films increase, while the CTE of FPI/APSZN hybrid films decreases. This study provides a novel approach to prepare low-κ FPI hybrids with enhanced properties.
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
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