CATALYSIS COMMUNICATIONS
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2024
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IF 3.4
Yang Zhang,Qizhuang Zou,Ruiqi Fang,Hua Tan,Hongbing Ji,Yingwei Li
Yolk-shell nanoreactors feature numbers of advantages in promoting catalytic performance. This work demonstrates the fabrication of yolk-shell Fe 3 O 4 @SiO 2 /Al 2 O 3 - T ( T = 500–900 °C) from metal-organic framework. Characterizations indicate the Fe 3 O 4 yolk and SiO 2 /Al 2 O 3 shell of the obtained nanoreactors. Fe 3 O 4 @SiO 2 /Al 2 O 3 –800 showed excellent performance in furfural acetalization to 2-(dimethoxymethyl)furan, achieving a 97% yield at 60 °C, atmospheric pressure within 5 h. Control experiments reveal the high reactivity of Fe 3 O 4 yolks for furfural acetalization, and acidic Al species are favorable for reactivity promotion. Besides, porous SiO 2 /Al 2 O 3 shells facilitate mass transfer and increase the accessibility of active sites, also contribute to the high performance and stability.
研究领域:
化学工程
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纳米材料科学
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催化反应
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
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2017
·Vol. 7
·期 55
·34609-34617
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IF 3.108
Xiang Ma,Xinyuan Zhou,Yan Gong,Ning Han,Haidi Liu,Yunfa Chen
ZnO/ZnFe2O4 hollow cube composites with heterogeneous structure are synthesized by a facile strategy through simple and direct pyrolysis of FeIII-modified Zn-based metal–organic frameworks. The as-synthesized ZnO/ZnFe2O4 hollow cubes have well-defined cube morphology with an ∼2 μm and multiple porous shell constructed from interpenetrated ZnO and ZnFe2O4 heterogeneous nanoparticles, providing structurally combined mesoporous channels for facilitating the diffusion and surface reaction of gas molecules. In addition, a comparative sensing performance investigation between ZnO/ZnFe2O4 hollow cubes and singular ZnO demonstrates that, in contrast with ZnO, the ZnO/ZnFe2O4 hollow cubes show significantly enhanced chemical sensing sensitivity towards low-concentration acetone. Furthermore, the ZnO/ZnFe2O4 hollow cubes exhibit good reproducibility and selectivity towards gaseous acetone. The enhanced sensing performance of the MOF-derived ZnO/ZnFe2O4 hollow cubes is ascribed to the unique hierarchical structure with high specific surface area, abundant exposed active sites with surface-adsorbed oxygen species and heterojunctions formed at the interfaces between ZnO and ZnFe2O4.
研究领域:
材料科学
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传感器技术
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纳米科技
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2010
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IF 0
Ying Chen,Xianchuang Zheng,Hanqing Qian,Zhiqing Mao,Dan Ding,Xiqun Jiang
Poly(acrylic acid) (PAA) nanogels with a hollow core−porous shell structure were prepared by the direct polymerization of an acrylic acid monomer in the presence of hydroxypropylcellulose (HPC) and a cross-linking agent, N,N-methylenebisacrylamide, followed by removal of HPC from the generated HPC−PAA nanoparticles in a basic environment. The properties of PAA nanogel were characterized by dynamic light scattering, FT-IR, transmission electron microscopy, and atomic force microscopy. It is found that the nanogels have a hollow core−porous shell structure. Protein, bovine serum albumin (BSA), and an antitumor agent, doxorubicin hydrochloride, were used as model drugs to investigate their loading abilities as versatile drug-delivery vehicles. The nanogel exhibits surprisingly high loading ability to both protein and small molecular drugs. For example, the maximum BSA loading capacity of PAA nanogel can reach as high as 800% (i.e., 1 mg of nanogel can load about 8.0 mg of BSA). This high loading capacity may be related with the hollow core−porous shell structure of PAA nanogels. PAA nanogels have also shown sustained drug release properties and can cross biological barriers to deliver loaded cargo inside cells. Considering the high stability of the materials, simple and mild preparation procedure, high loading capacity, sustained-release property, and ability to protect biological agents from denaturation, PAA nanogels should be promising drug-delivery carriers for drug-delivery systems.
研究领域:
材料科学
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生物医学工程
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药剂学
✓ 已验证
DOI
Journal of Physical Chemistry C
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2016
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IF 4.509
Zhi Zhu,Xu Tang,Su Kang,Pengwei Huo,Minshan Song,Weidong Shi,Ziyang Lu,Yongsheng Yan
A retrievability and successive degradation photocatalytic nanoreactor MS@FCN was first developed, which contained a magnetic photocatalytic core and mesoporous shell. The photocatalytic nanoreactor showed strong adsorption capacity, high activity, and good stability in degrading tetracycline. The nanoreactor can efficiently strengthen the binding abilities fixed to the tetracycline molecule and make the visible reflected in the confinement space for further enhancement of the absorption efficiency, which was confirmed by adsorption experiments and UV–vis DRS. Moreover, the mesoporous shell can protect the magnetic photocatalytic core inside for facilitating recycling and making the photocatalytic reaction cycle be carried out in and out of the microenvironment of the nanoreactor, which also was proved by cycling test and HPLC-MS. Therefore, this kind of ideal photocatalytic nanoreactor may offer a new opportunity to develop functional photocatalysts for complicated catalytic processes.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
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2017
·Vol. 5
·期 31
·16162-16170
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IF 8.867
Yajuan Hao,Xuan Jiao,Houbing Zou,Hengquan Yang,Jian Liu
The structure of biological components such as enzymes with active centers buried in hydrophobic pockets has inspired the design of new nanoreactors for efficient chemical processes. To address the current limitations of conventional hydrophobic catalysts or hydrophilic ones, herein, we reported the synthesis of core–shell structured catalysts with Pd-loaded fluoro-modified silica spheres as hydrophobic cores and mesoporous silicas as hydrophilic shells. The resultant nanoreactors allow the catalyst to not only be well dispersed in water but also be able to adsorb hydrophobic reactants to its active centers from water, which makes the catalyst exhibit much higher activity than its analogous catalyst Pd/SiO2 in the aqueous hydrogenation of olefins. Moreover, at the end of the reaction, we demonstrated that this nanoreactor can be directly used for the next reaction cycle after the removal of the upper layer of the organic product, making in situ catalyst recycling possible. Such a process significantly decreases the loss of the catalyst during recycling, which is unattainable for conventional catalyst separation methods such as filtration and centrifugation. After 12 reaction cycles, its activity has no significant decrease. These results illustrate the preparation of efficient solid catalysts for innovative green and sustainable chemical processes.
研究领域:
化学工程
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材料科学
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催化反应
✓ 已验证
产品关联
DOI
高影响因子
KINETICS AND CATALYSIS
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2013
·Vol. 54
·期 6
·716-723
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IF 0.543
Zeng Minfeng,Sun Xudong,Qi Chenze,Zhang Xian-Man
A novel and environmentally friendly heterogeneous catalyst has been prepared through the wet impregnation of copper(I) species onto the highly porous chitosan microspheres (CuI/PCMS). This novel CuI/PCMS heterogeneous catalyst with no additional ligands is much better than CuI homogeneous catalysts when applied in Heck reactions. Moreover, the reaction conditions are much milder than those for the similar copper catalysts mediated cross-coupling reactions reported in the literature. PCMS has been demonstrated not only the excellent solid support, but also have many unique functional groups to chelate the copper (I) species to enhance its catalytic activity.
研究领域:
催化化学
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有机合成
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材料化学
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环境友好化学
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功能高分子材料
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2015
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IF 2.711
J. Li,L.X. Chen,X. Li,C.C. Zhang,F.L. Zeng
In this study, a facile and effective surface hydrophobic layer protected selective etching strategy has been adopted to fabricate organic functionalized hollow silica nanospheres (OHSNSs). Our experiments demonstrated that the morphology and structure of OHSNSs were greatly affected by the types of organosilanes and concentrations of cetyltrimethylammonium bromide (CTAB) as pore-making agent. At low concentration of CTAB (1.9 mg/mL −1 ), it was found that the protective effect of the hydrophobic layer of 3-thiocyanatopropyltriethoxysilane (TCPTES) was so strong that can be endured long time etching (8 h), leading to the formation of hollow core and organic porous shell structure. And yet, the protective effect of the hydrophobic layer of vinyltriethoxysilane (VTES) was too weak to withstand alkali etching, resulting in preferentially etched of the outer vinyl protection shell. Whereas, at a higher concentration of CTAB (2.5 mg/mL −1 ), for TCPTES, the irregular and capsules-like spheres were obtained. In contrast, for VTES, porous core/solid shell structures with shell thickness of 16 nm were generated. In addition, no particles were observed when the CTAB concentration was above 2.5 mg/mL −1 .
研究领域:
纳米技术
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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
CARBOHYDRATE POLYMERS
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2020
·
IF 7.182
Jin Wang,Lehao Zhou,Qihao Sun,Haibo Cai,Wen-Song Tan
The proliferation and osteogenic differentiation of mesenchymal stem cells (MSCs) needed to be promoted for their use in stem cell-based therapy for large bone defects. This study aimed to prepare porous 2a-2 g scaffolds with antioxidant activity to reduce intracellular reactive oxygen species (ROS), which resulted in promoting the proliferation and osteogenic differentiation of MSCs. A series of novel chemically modified 2a-2 g scaffolds were fabricated by an acid-soluble/alkali-insoluble method. Besides, these 2a-2 g scaffolds had good biocompatibility, physicochemical properties and the ability to promote osteogenic differentiation of human adipose-derived stem cells ( h ADSCs). However, the proliferation ability of h ADSCs on 2a-2f scaffolds was weakened. Interestingly, 2 g scaffold had a positive effect on h ADSCs proliferation. These results indicated that the reduction of intracellular ROS was not conducive to h ADSCs proliferation but beneficial to h ADSCs osteogenic differentiation. Taken together, these significant results highlighted potential therapeutic benefit of 2 g scaffold in large bone defects.
研究领域:
生物材料
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干细胞研究
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组织工程
✓ 已验证
DOI
PubMed
高影响因子
Science China-Technological Sciences
·
2024
·
IF 4.4
Zhang YingXin,Liu HanGuang,Jin ShunYu,Li YaJuan,Zhang Wan,Zhou Hang,Nie ZanXiang,Huang Yuan
Wearable pressure sensors made from conductive hydrogels hold significant potential in health monitoring. However, limited pressure range (Pa to hundreds of kPa) and inadequate antibacterial properties restrict their practical applications in diagnostic and health evaluation. Herein, a wearable high-performance pressure sensor was assembled using a facilely prepared porous chitosan-based hydrogel, which was constructed from commercial phenolphthalein particles as a sacrificial template. The relationship between the porosity of hydrogels and sensing performance of sensors was systematically explored. Herein, the wearable pressure sensor, featuring an optimized porosity of hydrogels, exhibits an ultrawide sensing capacity from 4.83 Pa to 250 kPa (range-to-limit ratio of 51,760) and high sensitivity throughout high pressure ranges (0.7 kPa −1 , 120–250 kPa). The presence of chitosan endows these hydrogels with outstanding antibacterial performance against E. coli and S. aureus , making them ideal candidates for use in wearable electronics. These features allow for a practical approach to monitor full-range human motion using a single device with a simple structure.
研究领域:
材料科学
·
生物医学工程
·
可穿戴技术
·
健康监测
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）