JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
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2019
·Vol. 91
·期 1
·44-53
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IF 1.986
Cai Huafei,Jiang Yonggang,Li Liangjun,Feng Junzong,Feng Jian
Abstract Monodispersed silica sol with a small particle size, narrow size distribution, and high conversion was prepared via a modified Stöber method, and an orthogonal test method was used to investigate the influence of TEOS concentration, R (H 2 O/TEOS), ammonia concentration, and reaction temperature on the particle size, size distribution, and conversion of silica sol. It was found that the remarkable factors affecting the particle size from a large to a small order were ammonia concentration, reaction, temperature, and R (H 2 O/TEOS) value; similarly, the remarkable factors affecting the silica sol conversion from a large to a small order were the R (H 2 O/TEOS) value and reaction temperature in decreasing order of influence. None of the factors investigated in this study exhibited a significant effect on the particle size distribution. The optimal synthesis conditions for the preparation of monodispersed silica sol with small particle size and high conversion were as follows: TEOS concentration = 0.4 mol/L; R (H 2 O/TEOS) = 60; ammonia concentration = 0.10 mol/L; reaction temperature = 75 °C. The average particle size of monodispersed silica sol under optimum conditions was 5.25 ± 0.77 nm, and the conversion was 94.05%. Besides, this study also provides a systematic experimental and theoretical basis for the preparation of different particle sizes monodispersed silica sol with high conversion.
Monodispersed silica sol with small particle size, narrow size distribution and high conversion was prepared via a modified Stöber method, and orthogonal test method was used to investigate the influence of TEOS concentration, R (H 2 O/TEOS), ammonia concentration and reaction temperature on the particle size, size distribution and conversion of silica sol. Under the optimum conditions, the monodispersed silica sol with 5.27 ± 0.82 nm average particle size and 94.05% conversion rate was obtained.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
COLLOID AND POLYMER SCIENCE
·
2014
·Vol. 292
·期 6
·1385-1393
·
IF 2.41
Li Qiu-Ping,Yan Bing
The luminescent nanoparticles were prepared by encapsulating the [LnL 4 ] − (Ln = Eu, Tb; L = BTFA, HFAA, TTFA, TFAA) complexes anion into the silicon framework. We firstly synthesized a series of novel siloxy-bearing lanthanide complex precursor, and then encapsulated them into the silica sphere by a modified Stöber process. As a result, four europium and two terbium tetrakis β-diketonate complexes functionalized silica sphere nanoparticles were obtained and characterized in detail using Fourier transform infrared spectra, X-ray diffraction, scanning electronic microscope, thermogravimetric analysis, luminescence excitation and emission spectroscopy, luminescence lifetime measurements, and diffuse reflectance UV–Vis spectroscopy. The result shows that these luminescent nanoparticles maintain the distinctive luminescence character of lanthanide chelate including broad excitation spectra, line-like emission spectra, high quantum efficiency, and long luminescent lifetime, which makes them great potential application in the synthesis of luminescent nanoparticle.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2023
·Vol. 109
·期 2
·421-432
·
IF 2.5
Li Hongqing,Xu Wenqi,Xu Jiaqi,Zhu Mengxuan,Wang Rui,Jiang Heng,Jin Changzi
The nanoreactors with yolk-shell configuration have been one of the most attractive objects because of their unique performance in specific reactions. However, complicated synthesis procedures have restricted the truth understanding and wide application of the yolk-shell architectures. This article presents a universal and facile sol-gel process for fabrication of mesoporous silica hollow structure and derived yolk-shell composites with extended Stöber resorcinol-formaldehyde resin as sacrificed template. The crucial influence factors for the morphology of products are investigated. A series of yolk-shell composites with multitudinous components have been successfully designed and are further catalytic tested by different reactions. This work has provided a universal avenue for the fabrication of yolk-shell nanoreactors to suit specific reaction needs. Graphical
研究领域:
材料科学
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纳米技术
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化学工程
·
催化
✓ 已验证
DOI
高影响因子
Journal of Water Process Engineering
·
2025
·
IF 6.7
Zhiqun Xu,Lina Han,Ying Yang,Lei Li,Bing Wang,Jiancheng Wang,Weiren Bao,Liping Chang
The persistent threat of emerging contaminants (ECs) in aquatic ecosystems necessitates advanced water purification strategies. Peroxymonosulfate (PMS)-activated advanced oxidation processes (AOPs) have emerged as promising solutions, where non-metallic heteroatom-doped carbon catalysts demonstrate enhanced PMS activation capabilities. However, reconciling high catalytic efficiency with long-term stability in metal-free systems remains challenging. Herein, we develop monodisperse nitrogen-doped carbon nanospheres (NCS) through a facile in situ doping strategy. This approach involves the synthesis of spherical resorcinol-formaldehyde resin via the Stöber method using resorcinol as the carbon source and melamine as the nitrogen source, followed by controlled carbonization. By systematically adjusting the resorcinol/melamine ratio, we achieved precise regulation of nitrogen configurations, obtaining NCS-3 with optimal N content (5.3 at %). Remarkably, the NCS-3/PMS system exhibited ultrafast bisphenol A (BPA) degradation (100 % removal within 15 min, rate constant = 0.346 min −1 ) across a broad pH range (3.0–11.0), while maintaining exceptional tolerance to coexisting anions. Through multi-spectroscopic investigations and mechanistic analyses, we elucidated a dual-pathway activation mechanism: Dominant nonradical process mediated by singlet oxygen ( 1 O₂) synergized with auxiliary radical pathway (O 2 ·- ). Experimental and theoretical evidence confirmed that pyridinic N serves as the primary catalytic center, promoting PMS adsorption/activation through enhanced charge redistribution. This work provides critical insights for designing high-performance metal-free catalysts and advances the mechanistic understanding of active site engineering in carbon-based PMS activation systems.
研究领域:
环境科学
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材料化学
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催化
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水处理
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纳米技术
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产品关联
DOI
高影响因子
Journal of Macromolecular Science Part A-Pure and Applied Chemistry
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2024
·
IF 2.1
Yuan Ma,Lujie Wang,Haowen Wu,Qian Zhao,Jiying Men
Firstly, the SiO2 microspheres were prepared by Stӧber method, and then modified by 3-Aminopropyltrimethoxysilane (KH-540) to introduce –NH2 onto the microspheres. Then, SiO2-NH2 microspheres were mixed into polysulfone casting solution, and SiO2-NH2/PSF composite membrane was prepared by the phase conversion method. On this basis, the functional adsorbent SiO2-NH2/PSF-g-PMAA was prepared by grafting polymerization of methacrylic acid (MAA) as a functional monomer using –NH2/S2O82− surface initiation system. The samples were characterized by Fourier infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), the Brunauer–Emmett–Teller (BET) and weighing method. The adsorption properties of amlodipine (ADP) by functional adsorbents were investigated, and the adsorption mechanism was further studied. The results show that the adsorption reaches equilibrium at 180 min, and the adsorption kinetics can be well fitted by the pseudo-second-order model. The adsorption capacity of SiO2-NH2/PSF-g-PMAA for amlodipine in methanol with 1.4 mg/mL at 15 °C is 137 mg/g. The adsorption ability increases with the decrease of ionic strength and temperature via the hydrogen bond and ionic interactions, and the adsorption of ADP by SiO2-NH2/PSF-g-PMAA is consistent with the D-R adsorption isotherm model. Thermodynamic parameters imply that adsorption is a spontaneous and exothermic process.
研究领域:
材料科学
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高分子化学
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环境科学
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化学工程
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膜技术
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吸附科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）