CONSTRUCTION AND BUILDING MATERIALS
·
2017
·
IF 3.169
Jinfeng Sun,Kai Xu,Chaoqi Shi,Jian Ma,Weifeng Li,Xiaodong Shen
TiO 2 @SiO 2 nanoparticles with a core/shell structure widely used in photocatalytic fields were used in this paper to improve the hydration properties of the Portland cement. To this end, the core/shell TiO 2 @SiO 2 nanoparticles were synthesized first and then characterized by a series of techniques including transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR) and X-ray photoelectron spectra (XPS). Second, the influence of the core/shell TiO 2 @SiO 2 nanoparticles on cement hydration was investigated and compared with nano-TiO 2 through isothermal calorimetry, XRD, thermo gravimetric/derivative thermo-gravimetric (TG/DTG) and mercury intrusion porosimetry (MIP) analyses. The results showed that an amorphous SiO 2 layer can be deposited uniformly on nano-TiO 2 particles by forming new Si O Ti chemical bonds at the interface between the SiO 2 coating layer and nano-TiO 2 particle surface. This uniform layer was conducive to decrease the aggregation of nano-TiO 2 effectively. Compared with nano-TiO 2 , the core/shell TiO 2 @SiO 2 nanoparticles exhibited better hydration properties in terms of accelerated cement hydration, higher degree of hydration and lower porosity, even though both particles modified cement hydration.
研究领域:
材料科学
·
土木工程
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2024
·
IF 6.5
Le Zhang,Rui Li,Hao Ding,Daimei Chen,Xuan Wang
Coatings with superamphiphobicity and photocatalytic degradation properties to achieve excellent self-cleaning performance have received extensive attention. Herein, TiO 2 -SiO 2 composite particles with micro-/nanoscale hierarchical structures were fabricated by hydrophobic agglomeration. The TiO 2 -SiO 2 was modified with 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (PFDTS), and then it was sprayed onto the surfaces of substrates to obtain TiO 2 -SiO 2 /PFDTS coatings. The coating surface exhibited superamphiphobicity and low adhesion properties. The contact angles (CAs) of water, ethylene glycol, glycerol, and hexadecane on the coating surface were 163.5°, 154.6°, 157.3°, and 150.2°, respectively. The slide angles (SAs) of the above droplets on the coating surface were 0.4°, 2.7°, 1.6°, and 11.1°, respectively. In addition, 80.9 % methyl orange solution (10 ppm) was degraded by the TiO 2 -SiO 2 /PFDTS under UV irradiation in 60 min, demonstrating an excellent photocatalytic degradation performance. It also had good adaptability to different substrates, liquids with different properties, and outdoor environments. The results of a mechanistic study showed that SiO 2 and TiO 2 were connected by the carbon chains of modifiers. PFDTS and TiO 2 -SiO 2 might be combined by chemical bonds or surface carbon chains. The hierarchical structure of TiO 2 -SiO 2 and the low surface energy of PFDTS resulted in the superamphiphobic property of the TiO 2 -SiO 2 /PFDTS coating.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2022
·Vol. 107
·期 1
·178-189
·
IF 2.606
Li Qing,Qian Fuping,Yuan Ke,Dong Wei,Han Yunlong,Lu Jinli
In order to solve the problem of blocking the filter media when bag filters are used to deal with high-humidity dust, hydrophobic surface-modified filter media were prepared. Here we constructed a multi-layer rough structure using TiO 2 and SiO 2 , with polydimethylsiloxane (PDMS) subsequently deposited to reduce its surface energy to prepare stable and robust TiO2–SiO2@PDMS modified superhydrophobic filter media. Through modification of the filter media, its surface was changed from superhydrophilic to superhydrophobic, and the water contact angle reached 158°. For the particles with 0.3 μm, the filtration efficiency and quality factor of the modified filter media are higher than those of the unmodified filter media at a flow velocity of 0.043–0.127 m/s, which improves the filtration performance of the filter media. In addition, the modified filter media has strong durability in harsh environmental conditions (such as mechanical wear, strong acid or alkali solution), and has excellent self-cleaning performance. Therefore, such superhydrophobic filter media have great potential for the application of bag filters in various industrial production processes.
Graphical abstract
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
KEY ENGINEERING MATERIALS
·
2015
·
IF 0
Yin Yan Ding,Bi Xu,Feng Yan Ge,Zai Sheng Cai
In this work, self-cleaning cotton fabrics were prepared based on the TiO2-SiO2-Polydimethylsiloxane (PDMS) composites. TiO2-SiO2 composites were synthesized by depositing TiO2 nanocrystals onto preformed porous SiO2 and PDMS was used to enhance the linkage between TiO2-SiO2 composites and cotton fabrics. The TiO2-SiO2-PDMS composites coated cotton fabrics show superhydrophobicity with a water contact angle of 157°because of the abundant of methyl groups and hierarchical roughness features of the coated cotton fabrics. Meanwhile, the TiO2-SiO2-PDMS composites coated cotton fabrics display photocatalytic property, which were analyzed based on the removal and degradation of rhodamine B (RhB) under ultraviolet light. Abrasion resistance test indicates that the coating possesses a good mechanically durability.
研究领域:
材料科学
·
纺织工程
✓ 已验证
DOI
Journal of the American Chemical Society
·
2019
·
IF 14.695
Shiqun Wu,Xianjun Tan,Juying Lei,Haijun Chen,Lingzhi Wang,Jinlong Zhang
Photodriven nonoxidative coupling of CH4 (NOCM) is a potential alternative approach to clean hydrogen and hydrocarbon production. Herein, a Mott–Schottky photocatalyst for NOCM is fabricated by loading Pt nanoclusters on a Ga-doped hierarchical porous TiO2–SiO2 microarray with an anatase framework, which exhibits a CH4 conversion rate of 3.48 μmol g–1 h–1 with 90% selectivity toward C2H6. This activity is 13 times higher than those from microarrays without Pt and Ga. Moreover, a continuous H2 production (36 μmol g–1) with a high CH4 conversion rate of ∼28% can be achieved through a longtime irradiation (32 h). The influence of Ga on the chemical state of a surface oxygen vacancy (Vo) and deposited Pt is investigated through a combination of experimental analysis and first-principles density functional theory calculations. Ga substitutes for the five-coordinated Ti next to Vo, which tends to stabilize the single-electron trapped Vo and reduce the electron transfer from Vo to the adsorbed Pt, resulting in the formation of a higher amount of cationic Pt. The cationic Pt and electron-enriched metallic Pt form a cationic–anionic active pair, which is more efficient for the dissociation of C–H bonds. However, the presence of too much cationic Pt results in more C2+ product with a decrease in the CH4 conversion rate due to the reduced charge-carrier separation efficiency. This study provides deep insight into the effect of the doping/loading strategy on the photocatalytic NOCM reaction and is expected to shed substantial light on future structural design and modulation.
研究领域:
材料科学
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催化化学
·
理论计算
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Research Express
·
2017
·Vol. 4
·期 12
·125503
·
IF 1.068
Jiaxi Liu,Gang He,Nan Lu,Jiangtao Li
Photo-absorption enhanced black TiO2–SiO2 microspheres were prepared by flame spraying synthesis. The phase composition, microstructure, infrared absorption, and emission property of the synthesized samples were investigated. Compared with the rutile TiO2 raw material, the visible light and near-infrared absorptivity of the flame sprayed TiO2 is significantly enhanced. The addition of SiO2 promotes the rutile-to-anatase phase transformation and appearance of Ti3+ species. The prepared sample with a composition of 40 at.% TiO2–60 at.% SiO2 exhibits the highest absorption of above 95% in 0.79–2.5 µm, and the highest emissivity of above 0.96 in 3–5 µm and 8–14 µm. The black TiO2–SiO2 microspheres with enhanced photo-absorption properties can be used as a promising optical-thermal conversion material.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2019
·Vol. 43
·期 16
·6234-6241
·
IF 3.069
Xinfu Zhao,Wei Ju,Jian Zhang,Benxue Liu,Jing Zhang,Xibin Yi
TiO2/SiO2-Based nanocomposites with highly porous structures have received increasing attention due to their excellent photocatalytic activity. In this work, a TiO2/SiO2/Ag ternary composite aerogel with enhanced visible-light photocatalytic activity has been successfully synthesized through a facile sol–gel method combined with a supercritical drying technique. The specific surface area and pore structure of TiO2/SiO2/Ag aerogel could be controlled by adjusting the Si content. The TiO2/SiO2/Ag aerogel with pore size of 9.2 nm achieved the maximum adsorption capacity of oxytetracycline. The presence of SiO2 in TiO2/SiO2/Ag improved the compression strength of the aerogel and thus achieved long-term stability in photocatalysis. Furthermore, the addition of Ag particles in TiO2/SiO2/Ag effectively decreased the recombination of photo-electrons and holes. The photocatalytic degradation rates of oxytetracycline over the TiO2/SiO2/Ag aerogel with a mole ratio of Ag : Si : Ti = 0.1 : 10 : 4 were 3.1 and 2.3 times those over P25 and a TiO2/SiO2 aerogel. The enhanced photocatalytic performance of the TiO2/SiO2/Ag aerogel is attributed to the large specific surface area, 3-D porous structure, high electrical conductivity and compression strength of this novel composite aerogel.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2021
·
IF 5.161
Yi Wu,Kai Yan,Guilin Xu,Chenguang Yang,Dong Wang
Re-entrant geometries can effectively trap air pockets, increase air/liquid interface fraction, prevent the penetration of low surface tension organic liquids, and achieve super-oleophobic performance. However, the creation of re-entrant geometries usually involving expensive lithographic tools, or complicated chemical procedures, and cannot be applied on a large scale, such super-oleophobic surfaces are unsuitable for practical application. Constructing hierarchical micro/nanostructure on substrates is a feasible solution to achieve super-oleophobicity through facile spraying method. Herein, we report a super-oleophobic TiO 2 /SiO 2 composite coatings by taking advantage of an exceedingly simple spraying method. The dendritic structures produced by spraying the TiO 2 /SiO 2 mixture play the critical role in obtaining the re-entrant geometry required for oleophobic surface, and the introduction of micron-scale TiO 2 particles and nano-scale SiO 2 particles provide an enough dual-scale rough structure for the coating. The TiO 2 /SiO 2 composite coatings exhibit superior repellence to high and low surface tension liquids as well long-term durability. This design strategy may provide useful guidelines for the fabrication of particle-based spray-coated super-oleophobic surfaces.
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
JOURNAL OF NON-CRYSTALLINE SOLIDS
·
2023
·
IF 3.5
Lin Wang,Dehua Ma,Chonghe Xu,Luyi Zhu,Yadong Lv
In this study, we successfully fabricated TiO 2 /SiO 2 ceramic nanofibrous membranes with different molar ratios using a combination of electrospinning and sol-gel technology. The resulting nanofibers were composed of amorphous SiO 2 and fine-grained anatase; the amorphous SiO 2 served as a lubricating zone and refined the rutile grains in the nanofiber structure. The hybrid nanofibrous membranes exhibited exceptional mechanical properties: the highest average tensile strength was 3.22 ± 0.98 MPa, which is threefold higher than that of the TiO 2 nanofibrous membranes. Consequently, the TiO 2 /SiO 2 nanofibrous membranes withstood stretching, bending, folding, and compressing processes without breaking. Furthermore, the average reflectance of the TiO 2 /SiO 2 nanofibrous membranes exceeded 89.57% in the range of 500–2500 nm, and their thermal conductivity at room temperature was below 0.0310 W·m − 1 K −1 . The flexible and robust ceramic materials have significant potential for various applications such as thermal insulation, flexible energy, and wearable electronics.
研究领域:
材料科学
·
纳米技术
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Enqi Bu,Ying Chen,Chao Wang,Zhengdong Cheng,Xianglong Luo,Riyang Shu,Jingtao Zhang,Mingzheng Liao,Zhiqiang Jiang,Qingbin Song
Photoreforming of bio-derived liquids is anattractive approach toward sustainable H 2 production. Although a large number of bio-liquids are thermodynamically feasible for photocatalytic hydrogen production, few of them have been involved in this process due to their water insoluble nature. To achieve and promote the efficiency of photoreforming hydrogen production in bio-derived biphasic system, the Pickering interfacial catalysis was established over an amphiphilic Ag 2 O-TiO 2 /SiO 2 catalyst. In this case, the Ag 2 O-TiO 2 /SiO 2 sample was synthesized by means of an electrostatic self-assembly method by surface charge regulation of SiO 2 and the surface hydrophobic modification of Ag 2 O-TiO 2 /SiO 2 particles using a Pickering emulsion method. As shown in the results, the amphiphilic Ag 2 O-TiO 2 /SiO 2 particles were observed to successfully stabilize the bio-octanol/water emulsion. Even the complex structure and surface modification slightly reduce the light absorption efficiency and specific surface area of the catalyst, the hydrogen yield was greatly promoted over Ag 2 O-TiO 2 /SiO 2 compared to that of bare TiO 2 , Ag 2 O-TiO 2 and TiO 2 /SiO 2 . It was also discovered that the cyclic hydrogen production performance can be improved by simple re-emulsification. The effect of bio-octanol concentration for photoreforming was studied by a Langmuir-Hinshelwood-type kinetic model, and the reaction rate constant and bio-octanol adsorption constant were obtained. This study shows that photocatalyst after effective surface amphiphilic modification could provide a prospective approach for the hydrogen production from a bio-derived oil/water biphasic system under solar light.
研究领域:
能源科学
·
材料科学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2019
·Vol. 44
·期 4
·1194-1203
·
IF 3.069
Can Huang,Fengyi Wang,Daheng Wang,Zhiguang Guo
In this study, superamphiphobic coatings, which could repel liquids with a surface tension as low as 21.6 mN m−1 (n-octane), were prepared using a spray-coating method based on a flower-like hierarchical structure and highly fluorinated TiO2/SiO2 composite particles. And the coating exhibited broad liquid repellency to water-based composites, various oils, organic solvents and hot water. Moreover, the coating also possessed remarkable mechanical and chemical stability towards various forms of mechanical damage and in harsh chemical environments. Multiple features enable the coating to find more vital applications in antifouling, corrosion resistant, fuel transportation, gas adsorption, and protective coatings, etc.
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
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Liangyong He,Bin Yang,Sen Wang,Yuqing Yang,Yingying Wang,Haiyang Hu,Zhengzhi Zheng,Jiashuo Liu,Jiasheng Qian,Jibin Miao,Weiguo Zhang,Yuchao Ke
The increasing demand for improving the performance of optical devices and the development of nanotechnology have driven research on diffusion films. The preparation of diffusion films with well-defined microstructures can achieve uniform diffusion and scattering of light, thereby improving the efficiency and performance of optical devices. In this study, diffusion films with high transmittance and haze were prepared using PMMA@TiO2@SiO2 (P@T@S) composite microspheres, and the PMMA microspheres and nanoparticles were combined through electrostatic attraction. As compared with PMMA microspheres, the P@T@S composite microspheres displayed better heat resistance as well as swelling resistance. Optical performance data showed that the P@T@S diffusion film had the perfect optical performance with a transmittance up to 90.5% and a haze of 88.3%. The excellent light diffusion effect of the P@T@S diffusion film was experimentally demonstrated, with the light through the film not only displaying the largest area but also maintaining a relatively high brightness. Our findings can provide reference and guidance for further development of light diffusion films, which are of potential application in optoelectronic devices.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子