Chemistry-An Asian Journal
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2021
·Vol. 16
·期 19
·2952-2957
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IF 4.568
Fengwei Zhang,Mengmeng Liu,Qiang Liu,Jingjing Li,Boyang Li,Zhengping Dong
Graphical A facile and in-situ methanol-mediated strategy was proposed to fabricate Pd@ZIF-8 catalyst for efficient and size-selectivity alkenes hydrogenation. In-situ encapsulation of tiny and well-dispersed Pd nanoparticles (Pd NPs) in zeolitic imidazolate frameworks (ZIFs) was firstly achieved using a one-pot and facile methanol-mediated growth approach, in which methanol served as both solvent and a mild reductant. The microstructure, morphology, crystallinity, porosity as well as evolution process of the catalysts were determined by TEM, XRD, N 2 adsorption and UV-vis spectra. Due to the complete encapsulation of such Pd NPs combined with ultrahigh surface area and uniform microporous structure of ZIF-8, the resulting Pd@ZIF-8-60 min nanocomposite exhibited more superior catalytic activity for olefins hydrogenation with TOF of 7436 h −1 and excellent size selectivity than previously reported catalysts. Furthermore, the catalyst displays excellent recyclability for 1-octene hydrogenation and without any loss of the Pd active species.
研究领域:
材料科学
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催化化学
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产品关联
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2015
·
IF 3.453
Songlin Xue,Hong Jiang,Zhaoxiang Zhong,Ze-Xian Low,Rizhi Chen,Weihong Xing
A new Pd@ZIF-L hybrid catalyst having a unique crosshair-star shape with a size of about 20 μm was synthesized, in which a two-dimensional layered zeolitic imidazolate framework-L (ZIF-L) was used as a support to immobilize palladium nanoparticles via an assembly method. The hybrid catalyst with unique cushion-shaped cavities between layers with a size of 6.64 Å can be used for the diffusion of specific reactants not achievable by other ZIF systems such as ZIF-8. The crystal structure and morphology of Pd@ZIF-L are strongly dependent on the synthesis conditions. Palladium nanoparticles with an average size of 3 nm are homogeneously encapsulated in the ZIF-L crystals. The as-synthesized Pd@ZIF-L catalyst favors the conversion of alkenes with larger molecular sizes, and exhibits excellent molecule-size-selectivity and anti-leaching performance.
研究领域:
材料科学
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催化化学
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产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2019
·Vol. 21
·期 42
·6414-6422
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IF 3.382
Rui Zhang,Wanqing Song,Mingjing Wang,Huiming Ji
Metal–organic framework (MOF) materials with controlled microstructures have become popular in the last few decades. In this study, Zn-MOF precursors with diverse crystallinity and particle size (20–800 nm) were synthesized using an accelerating or retarding nucleation process by introducing various secondary ligands, which were employed as modulators in the coordination and ligand exchange equilibria according to their different acidity coefficients. Thus, the pore size of MOF-derived ZnO clusters was different, resulting in diverse gas sensing properties. Moreover, large precursor-derived ZnO-(2 and 3) assemblies with the micropore sizes of 1 nm and 0.75 nm showed size-selective sensing and better performance, which exhibited a higher and fast response (4 s) to butanone and n-butanol with the lengths of 0.664 nm and 0.499 nm, respectively, and a low limit of detection (0.1 ppm). This simple method of controlling the nucleation of MOFs and the pore size of ZnO assemblies paved a new way towards the design of the microstructure of MOF-based functional materials.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
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2013
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IF 4.187
Jiangping Xu,Yuanyuan Han,Jie Cui,Wei Jiang
A systematic study is conducted to reveal how far the polymeric vesicle wall can embed gold nanoparticles (AuNPs) with different sizes by combining experiments and self-consistent field simulations. Both the experimental and simulative results indicate that the location of AuNPs in vesicle wall or in spherical micelle is heavily size dependent. Whether the AuNPs enter the vesicle wall or not is determined by a ratio of the diameter of AuNPs (D0) to the thickness of the vesicle wall (dw0). The 1-dodecanethiol-coated AuNPs (AuxR) with D0/dw0 < 0.3 will stably disperse in the vesicle walls. For polystyrene-coated AuNPs (AuxS), a criterion of D0/dw0 is proposed based on the phase diagram; i.e., the AuxS with D0/dw0 < 0.5 can be located in the vesicle wall. Otherwise, the AuxR and the AuxS prefer to locate in spherical micelles. Moreover, the contributions of enthalpy and entropy to the total free energy of the system are respectively calculated to reveal the mechanism of the size selective distribution of AuNPs. The results demonstrate that the escape of AuNPs from vesicle walls and their selective distribution in spherical micelles is an entropy-driven process. Our study provides an important guideline for fabricating nanoparticle/block copolymer hybrid vesicles in dilute solution.
研究领域:
材料科学
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纳米技术
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聚合物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2019
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IF 7.015
Rui Zhang,Tianxu Zhou,Hongwei Peng,Min Li,Xuedong Zhu,Yuan Yao
A nano-porous and switchable pH-responsive polymeric membrane was fabricated through filtration technique with the assist of metal hydroxide nanostrands as template. A common used spherical polyelectrolyte brush (SPB), PAA@PS (poly (acrylic acid)) brushes grafted on polystyrene nanospheres , employed in this work as polymeric membrane. It features tunable pore size on line by shrinkage or stretching of PAA brushes under different pH value or ionic strength . Furthermore, both the length of PAA chains and the dimension of PS cores could tailor the pore size of the membrane effectively. These properties of PAA@PS membrane could separate nanoparticles within 10 nm with precise size-selective permeation. Meanwhile, since the membrane was endowed negative charge by PAA brushes, the membrane could adsorb and separate positive charge nanoparticles including dyes though the mixture solution effectively. Herein, this stimuli-responsive membrane is promising in the separation of ultrafine nanoparticles with precise size and charge selectivity.
研究领域:
材料科学
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化学工程
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生物分离技术
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
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2021
·Vol. 9
·期 40
·22871-22877
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IF 12.732
Yanqiu Wu,Muzaffar Ahmad Boda,Zhiguo Yi
Electrosynthesis of chemicals in parallel with hydrogen production exhibits distinct advantages: energy saving and generation of two value-added products. In this work, we first design an asymmetric neutral–acidic electrolytic cell by coupling the silver oxidation reaction (AOR) in a neutral anode chamber with the hydrogen evolution reaction (HER) in an acid cathode chamber. When the anode electrolyte contains a certain amount of chloride ions, AgCl particles can be steadily synthesized close to, but not in contact with, the silver electrode at a fixed voltage. This electrolytic cell requires a voltage of only 1.1 V to drive 10 mA cm−2. In order to simplify the system and reduce the cost, a symmetric acid membrane-free electrolytic cell is designed; this cell requires a voltage of only 0.95 V to drive 10 mA cm−2 and 1.37 V to drive 250 mA cm−2 when a silver rod and graphite rod are used as the anode and cathode, respectively. Besides high purity H2 generation at the cathode, the anode product is pure AgCl and its size can be controlled by changing the voltage. The Faraday efficiency is close to 95% for both H2 and AgCl generation.
研究领域:
化学工程
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材料科学
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能源技术
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产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2018
·Vol. 28
·期 34
·1802021
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IF 13.325
Rui Yan,Yang Zhao,Hong Yang,Xiao-Jing Kang,Chao Wang,Li-Li Wen,Zhen-Da Lu
Metal–organic frameworks (MOFs) hold great promise as porous matrixes for the incorporation of Au nanoparticles (NPs) because of their rationally designed framework structures. Unfortunately, the as-synthesized bulk MOFs usually vary in the range of micrometer or sub-micrometer size, rendering extremely longer molecular diffusion distance of chemical species. 2D MOF nanosheets with extended lateral dimensions and nanometer thickness are expected to implement fast kinetics and effectively lower mass-transfer barriers during embedding Au NPs process and sequential catalytic reactions. In this study, a novel 2D nanosheet of mixed-ligand Ni(II) MOF (referred to NMOF-Ni ) is successfully fabricated. With the merits of well-defined micropores and functional oxygen-decorated inner walls, the incorporation of quite monodisperse ultrasmall Au nanoparticles of around 1 nm into NMOF-Ni has been achieved for the first time. The resulting nanocomposites exhibit remarkable catalytic performance and good size selectivity toward aqueous reduction reactions of nitrophenol, taking advantage of ultrasmall Au and 2D nanosheet nature, as well as the intact microporosity of host matrix. The present encouraging findings might shed light on new ways to develop high-performance heterogeneous catalysts by using of 2D MOF nanosheets with functional cavities as hosts for homogeneous distribution of ultrasmall Au NPs.
研究领域:
材料科学
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催化化学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Sciences
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2019
·
IF 3.556
Qing Wu,Li He,Zhong Wei Jiang,Yang Li,Ting Ting Zhao,Yu Han Li,Cheng Zhi Huang,Yuan Fang Li
Efficient removal of non-biodegradable and hazardous dyes from wastewater remains a hot research topic. Herein, a rationally designed a Cu(II)-based metal–organic gel (Cu-MOG) with a nanoporous 3D network structure prepared via a simple one-step mixing method was successfully employed for the removal of cationic dyes. The Cu-MOG exhibited high efficiency, with an adsorption capacity of up to 650.32 mg/g, and rapid adsorption efficiency, with the ability to adsorb 80% of Neutral Red within 1 min. The high adsorption efficiency was attributed to its large specific surface area, which enabled it to massively bind cationic dyes through electrostatic interaction, and a nanoporous structure that promoted intra-pore diffusion. Remarkably, the Cu-MOG displayed size-selective adsorption, based on adsorption studies concerning dyes of different sizes as calculated by density functional theory . Additionally, the adsorption performance of the Cu-MOG still maintained removal efficiency of 100% after three regeneration cycles. These results suggested that the Cu-MOG could be expected to be a promising and competitive candidate to conveniently process wastewater.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF ANALYTICAL CHEMISTRY
·
2020
·
IF 0.936
Irfan AZHAR,Xin LIU,Hui-Yu HE,Qi-Shu QU,Li YANG
Portable microreactors (PMRs) have valuable applications in the field of proteomics. However, no PMRs have been developed for the size-selective proteolysis of low molecular-weight proteins (LWPs) with mass less than 30 kDa, which are of great importance in biomarkers, biomolecular signaling and the field of pathology. In this study, a novel syringe-filter-based PMR using core-shell mesoporous silica (CSMS) microspheres as an enzyme support was reported. Because of the unique properties of CSMS microspheres, the PMR was easily fabricated by on-site physical adsorption even without any incubation, which was accomplished by simply pushing trypsin solution through a syringe filter containing the microspheres. Efficient immobilization of trypsin was demonstrated by characterizing the PMR using various spectroscopic techniques. The PMR loading amount was approximately 2.9 mg/g trypsin/CSMS microspheres with negligible leaching. The capability of the proposed PMR for size-selective proteolysis was assessed by investigating the digestion of proteins with different molecular weights, i.e., cytochrome C (12.38 kDa), lysozyme (14.39 kDa), myoglobin (17.00 kDa) and ferritin (440.00 kDa). The results of capillary electrophoresis-electrospray ionization-mass spectrometry (CE-ESI-MS) analysis showed that, by using the proposed PMR, the peptide numbers and sequence coverage of LWPs in the sample were enhanced owing to the size-exclusion interaction of the mesopores against large proteins. The proposed PMRs had essential features of easy fabrication, low cost, reusability and efficient size-selective proteolysis, and performing multiple functions including size-exclusion of LWPs, trypsin digestion and filtration in a single injection step of protein samples. This study provided a robust approach for fabricating PMRs that could perform rapid size-selective digestion of LWPs.
研究领域:
生物化学
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分析化学
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蛋白质组学
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产品关联
DOI
高影响因子
RSC Advances
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2015
·Vol. 5
·期 14
·10393-10399
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IF 3.84
Lei Tan,Hai-Xia Wu,Mei-Yan Yang,Chuan-Jun Liu,Ren-Xi Zhuo
A drug delivery system of dual-stimulated release of size-selected cargos from β-cyclodextrin-covered mesoporous silica nanoparticles was prepared. Calcein loaded mesoporous silica nanoparticles (MSN) were capped by β-cyclodextrin (β-CD) through photocleavable moieties to control its release. Then the small size cargo p-coumaric acid (CA) was loaded. The cavity of β-cyclodextrin was blocked by ferrocene through the host–guest interaction between the ferrocene and β-cyclodextrin. The small cargo can be released by the escape of ferrocene under +1.5 V electro-stimuli. Calcein molecules could not pass through the cavity of the β-cyclodextrin due to its bigger size. The calcein was released from the MSN after the detachment of the β-cyclodextrin cap from the MSN surface with UV irradiation. Fluorescence spectra demonstrate that different sized cargoes were released successfully step by step under external UV-light and electro stimuli respectively.
研究领域:
材料科学与工程
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药物递送系统
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生物医学工程
✓ 已验证
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2024
·
IF 6.7
Jia Chen,Qi Liu,Yongchun Fu,Juan Xiang
Low-mass soluble β-amyloid peptide oligomers (LSAβOs) play a crucial role in the pathogenesis of Alzheimer’s disease. However, these oligomers exhibit heterogeneity in terms of structure, stability, and stoichiometry, and their abundance in biofluids is low, making accurate identification challenging. In this study, we developed a DNA nanocage-assisted method for selective sizing and sensitive quantification of LSAβOs in serum. Using LSAβO less than 10 kDa (LSAβO10kD) and less than 30 kDa (LSAβO30kD) as models, the size-matching rules between DNA nanocages and LSAβOs were investigated, and two appropriate nanocages were selected for the detection of two LSAβOs, respectively. Both nanocages were functionalized by encapsulating oligomer’s aptamer and a complementary sequence within their cavities. Once the LSAβO entered the corresponding nanocage cavity, the complementary sequence was released, triggering a hybridization chain reaction on an electrochemical sensing platform. The system achieved size-selective discrimination of LSAβO10kD with a linear range of 10–150 pM and LSAβO30kD with a linear range of 15–150 pM. Real sample testing confirmed the applicability of the method for blood-based diagnosis. The DNA nanocage-assisted electrochemical analysis platform provides an accurate, highly selective, and sensitive approach for oligomer analysis, which is significant for amyloid protein research and related disease diagnosis.
研究领域:
生物化学
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医学诊断
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2016
·
IF 3.782
Xinyun Zhu,Cai-Qi Wang
A pH and redox dual-responsive nanovalve with a long stalk was introduced on the surface of hollow mesoporous silica nanoparticles (HMSs-S1) to achieve cargo size selectivity delivery. The responsive nanovalve was designed by constructing of a stalk/β-cyclodextrins (CDs) supramolecular complex, which is based on an acid-labile acetal group and the host–guest interactions between β-cyclodextrins and ferrocenyl moiety (Fc). With stimulation by different pH and H 2 O 2 , Rhodamine 6G showed well-responsive behavior. On account of the long stalks of nanovalve, doxorubicin hydrochloride and 5-fluorouracil with different sized cargos are encapsulated in HMSs-S1 to test its behavior of cargo size-selective delivery. Moreover the HMSs-S2 with a short stalk based on β-CDs/Fc inclusion complex is synthesized to load small sized 5-FU drug as contrast experiment. Compared with HMSs-S2, HMSs-S1 is compatible with larger drug molecules such as Rhodamine 6G (R6G) and doxorubicin hydrochloride (DOX), while small sized 5-fluorouracil (5-FU) is unable to be sealed by the nanovalve. Dual responsiveness and drug size selectivity make mechanized HMSs possess potential applications in drug delivery system.
研究领域:
材料科学
·
药物递送系统
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纳米医学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）