COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2018
·
IF 2.829
Chao Hu,Wenhui Chen,Tan Li,Yanxi Ding,Han Yang,Shuangjie Zhao,Emmanuel Acheampong Tsiwah,Xiujian Zhao,Yi Xie
We present a cost-effective and environmentally friendly fabrication route for fluorine-free superhydrophobic SiO 2 -based films with robust mechanical properties on various substrates including soda-lime glass, fabric, paper and aluminium flake. The superhydrophobic dispersion is achieved by modifying the SiO 2 nanoparticles (NPs) with hexamethyl disilazane (HMDS), in which the SiO 2 NPs are derived from base catalyzed hydrolysis and condensation of tetraethoxysilane (TEOS). The water contact angle (CA) and sliding angle (SA) of the dip-coated films from the HMDS-modified SiO 2 NPs reache ∼170° and about 2°, respectively. We particularly present a facile route to greatly enhance the mechanical durability without noticeable lossing the superhydrophobicity of the films by mixing different size ranges of SiO 2 NPs in the presence ofhydroxy acrylic resin (HAR). The synthesized SiO 2 -based organic-inorganic composite superhydrophobic films display excellent self-cleaning properties even after 100 cycles of sandpaper abrasion. Combined with the excellent superhydrophobic properties and the robust mechanical properties, the present procedure provides a facile and cost-effective synthetic protocol of constructing surfaces for not only durable self-cleaning and antifouling devices but also anti-corrosion applications.
研究领域:
材料科学
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
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2018
·Vol. 135
·期 4
·2377-2387
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IF 2.209
Chen Juan,Zhang Wenbo,Liu Jing,Ge Heyi,Tian Moufeng,Liu Jianye,Jing Min
Phenolic resin (PR) modified with hybrids of reduced graphene oxide (RGO)-encapsulated nano-SiO 2 (SiO 2 –RGO) was prepared by a simple method. The synergistic effect of RGO and nano-SiO 2 was achieved in the thermal decomposition of the modified PR. Thermal stability of SiO 2 –RGO and the modified PR was evaluated by thermogravimetric analysis (TG). With 1 mass% loading of SiO 2 –RGO, the maximum decomposition temperature ( T dmax ) of the modified PR was increased by 32.50 °C and the residual mass at 800 °C was increased by 6.54%. The structure of the resin char was characterized to study the mechanism of ameliorative thermal stability. SiO 2 –RGO hybrids were conducive to induce the PR to form graphitized carbon in the pyrolysis process. Thus, SiO 2 –RGO can facilitate the application of PR in the fields of heat insulation and ablation resistance.
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
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
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2015
·Vol. 75
·期 1
·82-89
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IF 1.532
Xiao Zuo-Yi,Huang Shu-Xian,Zhai Shang-Ru,Zhai Bin,Zhang Feng,An Qing-Da
Abstract A one-pot method was introduced to fabricate Ag–SiO 2 hollow composite spheres with developed porosity by employing monodisperse carboxylic-capped polystyrene (PS–COOH) spheres as a hard template. During the synthetic process, Ag + ions were immediately anchored on the surface of the PS–COOH spheres via electrostatic interaction and readily reduced by employing polymethylhydrosiloxane (PMHS) as a reducing agent. At the same time, silica oligomers derived from the hydrolysis of PMHS and TEOS were slowly deposited on the PS–COOH spheres to form solid silica shells. Subsequent decomposition of the PS–COOH spheres in air induced the formation of Ag–SiO 2 hollow spheres. The as-prepared products were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and N 2 absorption–desorption study. The results show that the well-designed composite spheres featured thin and spherical silica shell (~10 nm), large surface area (>240 m 2 g −1 ) and mesopore (6.0–9.0 nm). In addition, the Ag–SiO 2 hollow composite spheres exhibited high catalytic performance toward the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). Graphical Abstract A one-pot method was reported to prepare Ag–SiO 2 hollow spheres with well-developed porosity, which exhibited high catalytic performance and durable activity for the reaction of 4-NP to 4-AP.
研究领域:
材料科学
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纳米技术
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
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2015
·
IF 5.636
Daifang Wang,Yanyan Li,Zhenyu Lin,Bin Qiu,Longhua Guo
Carcinoembryonic antigen (CEA) is recognized as a disease biomarker to reflect the existence of various cancers and tumors in the human body. Sensitive detection of CEA in body fluid is valuable for clinical diagnosis and treatment assessment of cancers. Herein, we present a new approach for ultrasensitive determination of CEA in human serum based on localized surface plasmon resonance (LSPR) enhanced electrochemiluminescence (ECL) of Ru(bpy)32+. In this surface-enhanced ECL (SEECL) sensing scheme, Ru(bpy)32+-doped SiO2 nanoparticles (Ru@SiO2) act as ECL luminophores, and AuNPs are used as LSPR source to enhance the ECL signal. Two different kinds of aptamers specific to CEA are modified on the surface of Ru@SiO2 and AuNPs, respectively. In the presence of CEA, a multilayer of Ru@SiO2–AuNPs nanoarchitectures would be formed. Our investigation reveals that the ECL signal of Ru@SiO2 can be effectively enhanced by AuNPs. One layer of Ru@SiO2–AuNPs nanoarchitectures would generate about 3-fold ECL enhancement compared with the ECL of the nanoarchitectures without the presence of AuNPs. As much as 30-fold ECL enhancement could be obtained by a multilayer of Ru@SiO2–AuNPs nanoarchitectures. Under the optimal conditions, a detection limit of 1.52 × 10–6 ng/mL of CEA in human serum was achieved. To the best of our knowledge, CEA assays with such a low LOD have never been reported for an ECL sensor.
研究领域:
分析化学
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生物医学工程
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肿瘤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER DEGRADATION AND STABILITY
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2015
·
IF 3.163
Hongchang Pang,Xuesong Wang,Xingkun Zhu,Peng Tian,Guiling Ning
An efficient halogen-free composite flame retardant (CFR) consisting of a brucite core and a thin SiO 2 shell was synthesized via a facile nanoengineering route. The as-synthesized CFR was employed as a filler material to improve the mechanical performance and flame retardancy of EVA composite. In comparison with that of EVA/brucite and EVA/PM, the mechanical properties of EVA/CFR, especially the tensile strength (TS), presented a remarkable increase reaching at least a 25% increment. Meanwhile, with the same 50 wt% of fillers, the EVA/CFR formulation could achieve a limiting oxygen index (LOI) value of 34 (13% higher than that of EVA/PM blends) and UL-94 V-0 rating. Moreover, the heat release rate (HRR), peak heat release rate (PHRR), total heat released (THR), smoke production rate (SPR) and mass loss rate (MLR) were considerably reduced. Based on the results, the enhanced mechanism for the mechanical properties and flame resistance of CFR particles has been also proposed, which could be mainly ascribed to structural synergy between brucite core and SiO 2 shell. Therefore, the nanoengineering of brucite@SiO 2 might pave the way for the future development of a facile large-scale approach to brucite-based flame retardant materials.
研究领域:
材料科学
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纳米技术
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防火材料
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
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2014
·
IF 1.968
Yanqing Wang,Hongmei Zhang
The effect of SiO 2 nanoparticle on the conformation and activity of catalase were studied and observed by UV–vis, circular dichroism, fluorescence spectroscopy and molecular modeling methods. All the experimental data showed that the spectral changes of catalase were induced by SiO 2 nanoparticle exposure. SiO 2 nanoparticle could bind to catalase by electrostatic, hydrogen bonding and hydrophobic forces. These interactions decreased the α-helices content of catalase, which had more unfolded and more flexible structure. These structural changes did not obviously affect the solvent polarity of environment around both Trp and Tyr residues on catalase. Moreover, the activity assay indicated that SiO 2 nanoparticle was an activator for catalase activity. In a word, the biomolecular structure changes revealed by spectra provided a better understanding of the nanotoxicity and potential health effects of SiO 2 NP exposure.
研究领域:
生物化学
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纳米毒理学
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分子生物学
✓ 已验证
产品关联
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
·
2014
·
IF 1.09
Zhanjun Wu,Min Wang,Zhi Wang
The mechanical and thermal properties of epoxy nanocomposites filled with 7–40 nm spherical silica particles were investigated as a function of silica loadings. Due to the ultrasonic dispersion and modification of the coupling agent, the silicon dioxide (SiO2) nanoparticles were readily dispersed in the epoxy resin with light aggregation for the loading of up to 5 wt% as determined using a scanning electron microscope (SEM). The tensile test indicated that the tensile strength and elongation at break of the nanocomposites increased by up to 23% and 31%, respectively, compared with the neat epoxy resin. The glass transition temperatures of all the epoxy nanocomposites were higher than that of the neat epoxy resin for about 35–45°C, but did not show significant changes with an increase in the silica loading. The fracture surfaces were also observed using SEM, which showed evidence of the SiO2 nanoparticle debonding.
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
COLLOID AND POLYMER SCIENCE
·
2017
·Vol. 295
·期 7
·1223-1232
·
IF 1.723
Yao Jia,Cao Zhihai,Chen Qun,Zhao Shuning,Zhang Yushang,Qi Dongming
Poly(styrene- co -methyl methacrylate) (poly(St- co -MMA))/SiO 2 nanocomposite particles (NCPs) were prepared through miniemulsion polymerization by using polyoxyethylene (20) sorbitan monolaurate (commercial name: Tween-20) as the sole surfactant. The number fraction of poly(St- co -MMA)/SiO 2 NCPs in the as-synthesized emulsion could exceed 90% in some well-designed systems, indicative of high efficiency of poly(St- co -MMA)/SiO 2 NCP formation. Each poly(St- co -MMA)/SiO 2 NCP contained many SiO 2 NPs, thus exhibiting a high composite efficiency between the poly(St- co -MMA) and SiO 2 NPs. The mechanistic investigation indicated that the enhanced efficiency of the poly(St- co -MMA)/SiO 2 NCP formation is due to the improved homogeneity in the distribution of SiO 2 among the monomer droplets and the effectively suppressed nucleation of plain monomer droplets through controlled coalescence of the monomer droplets with the latex particles.
研究领域:
材料科学
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化学工程
·
高分子化学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Advanced Materials Interfaces
·
2017
·Vol. 4
·期 15
·1700062
·
IF 4.279
Aijaz Ahmed Babar,Xianfeng Wang,Nousheen Iqbal,Jianyong Yu,Bin Ding
Liquid moisture (sweat) transport properties of textile materials play critical role in maintaining the comfort of body which are mainly controlled by surface chemistry, structure, and morphology of substrate. Herein, a dual layer surface treated nonwoven (NW)/electrospun nanofiber membrane with excellent differential liquid moisture transport characteristics is reported. NW is used as inner layer for its high moisture releasing and low moisture absorbing features, and polyacrylonitrile (PAN) as outer layer because of its decent hydrophilic nature. Wettability of NW is tailored by surface treatment with polydopamine, and the wicking characteristics of PAN nanofibers are enhanced by inducing hydrophilic SiO 2 nanoparticles (PAN-SiO 2 ). Performance of resultant surface treated NW (TNW)/PAN-SiO 2 nanofiber composite membranes is thoroughly characterized by moisture management tester (MMT). Subsequent composite membranes offer high wettability gradient which leads to their marvelous MMT performance with an outstanding one-way transport capacity of 1413%, excellent overall moisture management capacity of 0.99, and a decent water vapor transfer rate of 12.73 kg m −2 d −1 , indicating a potential candidate for faster sweat release applications.
研究领域:
材料科学
·
纺织工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Qiang Huang,Meiying Liu,Jiao Zhao,Junyu Chen,Guangjian Zeng,Hongye Huang,Jianwen Tian,Yuanqing Wen,Xiaoyong Zhang,Yen Wei
Polyethylenimine-tannins coated SiO 2 (SiO 2 @PEI-TA) hybrid materials have been prepared via a single-step multifunctional coating with polyethylenimine (PEI) and tannins (TA), and characterized by transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). The as-prepared SiO 2 @PEI-TA composites were examined as adsorbents to remove the Cu 2+ from aqueous solution. The effects of contact time, initial Cu 2+ concentration, solution pH and temperature, on Cu 2+ adsorption have been investigated. The results show that the adsorption of Cu 2+ onto SiO 2 @PEI-TA is dependent on the contact time, Cu 2+ concentration, pH and temperature. The SiO 2 @PEI-TA composites show a 2.4-fold increase in adsorption capacity, implying that the introduction of PEI-TA coating is in favor of the Cu 2+ adsorption. Based on the analysis of kinetic data, the kinetics of Cu 2+ adsorption is more accurately described by the pseudo-second-order model. The equilibrium data are analyzed by Langmuir and Freundlich isotherms. Results of isotherms show that the better agreement is Freundlich isotherm model with correlation coefficient of 0.9914, which suggests that the adsorption of Cu 2+ onto SiO 2 @PEI-TA is mainly a heterogeneous adsorption process. Thermodynamic analyses show that the adsorption interaction is actually a spontaneous and endothermic chemical process, which might involve the chemical chelation between Cu 2+ and functional groups (amine and carboxyl groups) on the surface of SiO 2 @PEI-TA. In addition, the Cu 2+ ions could desorb from SiO 2 @PEI-TA by using acid solution and the adsorption efficiency remains at high level after five adsorption-desorption recycles. These results provide potential applications of these novel adsorbents for the removal of heavy metal Cu 2+ from aqueous solution and also provide strong evidence to support the adsorption mechanism proposed in the study.
研究领域:
环境科学
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2018
·Vol. 10
·期 1
·59
·
IF 2.935
Wenqiang Wang,Xi Chen,Chu Zhao,Bowu Zhao,Hualin Dong,Shengkui Ma,Liying Li,Li Chen,Bin Zhang
A blend of Polyvinylidene Fluoride (PVDF) and SiO2microspheres inN,N-Dimethylformamide (DMF) underwent phase inversion to form a PVDF/SiO2membrane with SiO2microspheres in the membrane’s pores. Subsequently, the SiO2microspheres have been used as platforms for in site Ag nanoparticles (NPs) synthesis, forming a composite membrane. Benefitting from the full exposure of Ag NPs to the reactants, the composite membrane shows high catalytic reactivity when catalyzing the reduction ofp-nitrophenol under a cross-flow. The catalytic reaction follows the first-order kinetics, and the reaction rate increases with an increase in the amount of Ag NPs in the membrane, the reaction temperature, and the operating pressure. What is more, highly purified products can be produced and separated from the reactants in a timely manner by using the composite membrane.Keywords:Ag nanoparticles;catalysis;composite membrane;separation;SiO2microspheres
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SURFACE ENGINEERING
·
2018
·
IF 1.978
G. Luo,Z. Jin,Y. Dong,J. Huang,R. Zhang,J. Wang,M. Li,Q. Shen,L. Zhang
The wear resistance and transparency properties of superhydrophobicity are most important issue essential for the application of superhydrophobic materials in industry. In this paper, we successfully prepared good wear resistance PU/SiO2 (polyurethane/silica) composite superhydrophobic coating with the double-step sol–gel route. The PU and SiO2 coating occurs crosslinking reaction forming composite superhydrophobic coating. The superhydrophobic coating surface is characterised by environmental scanning electron microscope and other testing methods, the results show that the PU/SiO2 composite superhydrophobic coating surface has excellent superhydrophobic properties and the Sa value was 332.5 nm. We used the pressure of 5 KPa to verify the wear resistance which the PU/SiO2 composite superhydrophobic coating surface exhibits good wear resistance, the water contact angle (WCA) still remains 138.7° after the abrasion resistance test. The PU/SiO2 composite superhydrophobic coating has high transparency in the visible light. The largest WCA of PU/SiO2 composite superhydrophobic coating could reach 162.1°.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）