APPLIED THERMAL ENGINEERING
·
2025
·
IF 6.9
Hao Wang,Liu Yang,Xiaoke Li
Solar energy, recognized for its abundant and clean attributes, is a burgeoning renewable resource. Nanofluid photothermal conversion technology with volume absorption properties has been rapidly developed in recent years. This research optimized the performance of Ti 3 C 2 (MXene) nanofluid in solar photothermal conversion by integrating SiO 2 nanoparticles to form a composite nanofluid. The stability, thermal conductivity, and photothermal properties of the Ti 3 C 2 /SiO 2 nanofluids were comprehensively evaluated. The nanofluids demonstrated high stability, as evidenced by Zeta potentials all above 40 mV. Furthermore, the thermal conductivity of the nanofluids escalated with an increase in SiO 2 content. Specifically, the thermal conductivities of the composite nanofluids experienced an approximate 9 % enhancement when the temperature was elevated by 25 °C. The composite nanofluid had better light absorption because of SiO 2 nanoparticles’ forward scattering ability. The most efficient mixture (Ti 3 C 2 : 40 ppm and SiO 2 : 1000 ppm) reached a 67.35 % photothermal conversion efficiency, which is 5 % higher than the Ti 3 C 2 nanofluid alone at the same concentration. Rather than solely enhancing light absorption, this study provides a new pathway to improve the photothermal conversion efficiency of nanofluids by strengthening scattering. This contributes to enriching the theoretical and practical understanding of nanofluids in the field of photothermal conversion, offering scientific evidence and technical support.
研究领域:
材料科学
·
太阳能技术
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Yihui Ma,Fangli Zhang,Kun Chen,Yue Zhou,Zhaohui Wang,Zhaoliang Cui
As a new separation technology, membrane condensation requires simple equipment and mild operating conditions and has wide application potential and value in the process of water vapor recovery and chemical concentration and recovery. In this paper, we have proposed a new application process to incorporate nano-SiO2 into ECTFE membranes and apply them in the membrane condensation process. The fabrication of ethylene-chlorotrifluoroethylene copolymer (ECTFE)/SiO2 hybrid membranes is performed by incorporating hydrophobic nano-SiO2 during ECTFE membrane preparation, with varying ECTFE/SiO2 compositions achieved through SiO2 dosage adjustments. It can be found that SiO2 can change the structure of membrane during the process; hence, the impact of SiO2 removal after membrane formation on membrane performance was evaluated. SiO2 removal was conducted using a 1 mol/L hot alkali solution with continuous agitation for 24 h. A maximum water recovery rate of 24% (adequate for industrial water self-sufficiency) was attained at 2 wt % SiO2. Compared with the original membrane, the addition of hydrophobic nano-SiO2 significantly enhances the condensation performance of the ECTFE membrane.
研究领域:
化学工程
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材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2019
·
IF 2.781
Hong Lei,Tingting Liu,Lei Xu
SiO 2 abrasive is one of the most effective abrasives used in chemical mechanical polishing (CMP) due to its uniform size, good dispersibility and good chemical reactivity. In this paper, a series of novel Sm-doped colloidal SiO 2 composite abrasives were synthesized by seed-induced growth method. The composite abrasives were characterized by using scanning electron microscopy, time-of-flight secondary ion mass spectrometry analysis (TOF-SIMS) and X-ray photoelectron spectroscopy (XPS). The structure of the composite abrasive is core-shell type with silica as a core and a coated growth layer (including SiO 2 , Sm 2 Si 2 O 7 and Sm(OH) 3 as shell via chemical bonds and hydrogen bonds . The CMP properties of the composite abrasives on sapphire substrates were further studied and the results show that the Sm-doped colloidal SiO 2 composite abrasives give lower polished surface roughness (Ra) and higher MRR than that of the pure colloidal SiO 2 abrasive under the same polishing conditions. By TOF-SIMS and XPS analyses on the polished slurries, the acting mechanisms of Sm-doped colloidal SiO 2 composite abrasives on sapphire were explored also.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Huijuan Liu,Keyan Wei,Chao Long
Y zeolite with high specific surface area and peculiar microporous channels has been regarded as a promising adsorbent in volatile organic compounds (VOCs) control. However, a scalable strategy for improving the hydrophobicity and mass diffusion of Y zeolite to remove VOCs remains a challenge. In this study, we successfully synthesized two NaY@ meso -SiO 2 core–shell composites with different shell thicknesses by coating NaY zeolite with mesoporous SiO 2 (NaY@ meso -SiO 2 -0.8 and NaY@ meso -SiO 2 -1.2), which significantly improved the hydrophobicity of NaY zeolite and diffusion of VOCs into NaY zeolite. The results of XRD, SEM, TEM, FTIR and BET confirmed the successful synthesis of core–shell composites. The adsorption equilibrium experiments showed that coating NaY zeolite with mesoporous SiO 2 effectively enhanced the hydrophobicity of NaY zeolite. Under RH = 0, the adsorption capacity of pristine NaY zeolite was the highest; while under RH = 50%, NaY@ meso -SiO 2 -1.2 exhibited stronger adsorption ability and excellent hydrophobicity. The adsorption diffusion indicated that coating NaY zeolite with mesoporous SiO 2 remarkably promoted the diffusion of VOCs into composites. Compared with the pristine NaY, core–shell composites showed higher diffusion coefficients and lower diffusion activation energy under RH = 0, particularly NaY@ meso -SiO 2 -1.2. In addition, linear solvation energy relationships (LSERs) revealed that π-/n-electron pairs interaction became weak and dipolar interactions were enhanced when water was adsorbed on the surface of NaY@ meso -SiO 2 -1.2. Hydrogen bonding decreased when RH level reached 50% and then increased with the increase of RH from 50% to 90%.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Chao Wang,Nankun Chen,Yiyao Xiao,Jiahao He,Rui Han,Ningning Song
Fe 3 O 4 @SiO 2 composites with different morphologies (hollow nanorods , porous nanorods, and flower-like nanoparticles) were constructed using different preparation methods. Considerably enhancement of resonance frequency and permeability beyond Snoek’s limitation were observed in the Fe 3 O 4 @SiO 2 composites with shape anisotropy and porous core-shell nanostructure . The resonance frequency of porous Fe 3 O 4 @SiO 2 nanorods enhanced to 4.21 GHz, which is much higher than the natural resonance frequency of 1.2 GHz for Fe 3 O 4 bulk. The minimum reflection loss (RL min ) of Fe 3 O 4 @SiO 2 porous nanorods reached -59.49 dB at 8.89 GHz, and its effective bandwidth (RL < -10 dB) covered 4.52 GHz at a thickness of 3.18 mm. In addition, the radar scattering cross section (RCS) reduction value reached more than 48 dBm 2 after removing the background. Our study provides insight into the relationship between anisotropy, core-shell structure, morphology of nanoparticles and corresponding microwave performance, and provides a reference scheme for the fabrication of high-performance lightweight microwave absorbing materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2018
·Vol. 87
·期 3
·734-742
·
IF 1.745
Wang Xiaoqing,Wu Zongxiao,Zhi Mingjia,Hong Zhanglian
Abstract We reported the preparation of a series of ZrO 2 -SiO 2 composite aerogels via the sol-gel reaction between the zirconium source (ZrOCl 2 ·8H 2 O) and the gel initiator (mercaptosuccinic acid-triethoxyvinylsilane). Such novel gel gelator was prepared by the thiol-ene click reaction using triethoxyvinylsilane (VTES) and mercaptosuccinic acid (MSA). The unique molecule structure of the gel initiator allows the in-situ modification of ZrO 2 with SiO 2 in the sol-gel reaction, which was achieved by the hydrolysis and polycondensation of siloxane with the change of the pH spontaneously. SiO 2 with the controllable content can be in-situ introduced into ZrO 2 backbone. As a result, the composite aerogel showed better thermal stability compared with pristine ZrO 2 aerogel, proved by the following facts: (i) the aerogels remained amorphous after calcination in air at 600 °C; (ii) the specific surface area maintained at 53.4 m 2 /g when the temperature rising to 1000 °C.
ZrO 2 -SiO 2 composite aerogels with improved thermal stability have been prepared via the “thiol-ene” click section
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
International Journal of Polymer Science
·
2024
·
IF 3.4
Shuangjie Liu,Jialin Yu,Yongping Hao,Feng Gao,Mo Zhou,Lijun Zhao
Using Nafion212 membrane and TEOS solution as raw materials, Nafion212/SiO2 composite membranes were prepared. In the in situ sol-gel reaction process, a series of Nafion/SiO2 composite membranes were prepared by varying the reaction temperature and reaction time. The effects of different modification schemes on Nafion/SiO2 composite membranes were studied using SEM, EDS, TEM, TGA, XRD, and mechanical tensile experiments, among other methods. The results show that Nafion/SiO2 composite membranes prepared at 3°C exhibit a well-separated phase structure and excellent water retention properties, with a water uptake of 29.23% and a swelling ratio of 24.25%. These membranes also demonstrate outstanding physical and chemical performance, with a maximum tensile stress of 13.6 MPa and an elongation at a break of 270%. At 110°C, the proton conductivity of the Nafion/SiO2 composite membrane reaches 0.172 S/cm, meeting the requirements for high-temperature proton exchange membrane fuel cells.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Lin Qiao,Dong Fu
N-doped carbon-silicon composite adsorbent (NC@SiO 2 ) has garnered significant attention in the field of CO 2 capture. In this study, a novel NC@SiO 2 has been developed by combining hydrothermal synthesis, Stober method, and one-step carbonization activation. It exhibits a moderate static adsorption capacity (3 mmol/g, 298.15 K) , along with low adsorption heat (14.65–21.93 KJ/mol). At 313.15 K, the dynamic adsorption capacity and adsorption rate for CO 2 (volCO 2 : volN 2 = 15 %:85 %) are 2 mmol/g and 0.202 mmol/g/min, respectively. Additionally, it demonstrates excellent cycle stability, with the adsorption capacity decreasing by only 7 % after 10 cycles. Density Functional Theory (DFT) calculations confirm that the presence of functional groups of N and O significantly enhances CO 2 adsorption performance of NC@SiO 2 . The synergistic effect of SiO 2 coating, N doping, and K 2 CO 3 activation is important for improving CO 2 dynamic adsorption performance, positioning NC@SiO 2 as a promising candidate for capturing CO 2 from flue gas.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Physica Status Solidi-Rapid Research Letters
·
2018
·Vol. 12
·期 10
·1800319
·
IF 3.721
Bismark Boateng,Gaolong Zhu,Weiqiang Lv,Dongjiang Chen,Chao Feng,Muhammad Waqas,Shamshad Ali,Kechun Wen,Weidong He
A highly uniform, heterogeneous-phase composite separator is synthesized by a direct post-solidation process from the mixture of nano-SiO 2 /acetone monodisperse suspension and poly(vinylidene fluoride- co -hexafluoropropylene) (PVDF- co -HFP)/acetone gel, without any organic surfactants. This technique leads to the PVDF- co -HFP/SiO 2 composite separator outstanding microstructural uniformity. The incorporation of SiO 2 nanoparticles leads to reduced crystallinity (≈27%), enhanced wettability (≈14%), improved electrolyte uptake (≈420%), and enhanced mechanical strength (>14 MPa) of the composite separator. These enhanced properties of the separator translate into remarkable LiFePO 4 /Li battery performance with reduced polarization, a high room-temperature capacity of 165 mAh g −1 at 0.5 C, a high thermal dimensional stability (≈4.5% shrinkage after annealing at 160 °C for 1 h) and 5.2% capacity degradation after 1500 charge/discharge cycles at 2 C.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2022
·
IF 7.693
Qiang Gao,Xiaomei Wu,Fangya Shi
In recent years, cool building materials have received increasing attentions due to their superior energy-saving efficiencies. In this work, novel self-cleaning cool coatings based on fluorocarbon resin-montmorillonite (MMT)/SiO 2 composites were prepared for energy-saving buildings. The intercalation modification of MMT improved the dispersion stability of MMT in organic solvent. Surface modification of MMT and SiO 2 particles by fluoroalkyl silane (FAS) produced hydrophobic particles. Fluorocarbon resin was used as a binder. With the assistance of the micro/nano structure of montmorillonite/SiO 2 composites and low surface energy of FAS and fluorocarbon resin, superhydrophobic state of the MMT/SiO 2 composite coatings can be achieved. The maximum contact angle of the MMT/SiO 2 composite coatings was as high as 163.5°. The superhydrophobic composite coatings exhibited superior self-cleaning property and good mechanical durability. Furthermore, the NIR solar reflectance of the superhydrophobic montmorillonite/SiO 2 composite coatings ranged from 0.77 to 0.85. The composite coatings reduced the heat box’s inside temperature of by 5.9℃. Therefore, the integration of high NIR reflectance property and superior self-cleaning property makes montmorillonite/SiO 2 composite coatings good candidates as self-cleaning cool roof coatings for energy-saving buildings.
研究领域:
材料科学
·
能源与环境工程
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2022
·Vol. 16
·期 1
·201
·
IF 3.748
Luping Tang,Chen Liao,Yingqing Guo,Yangyang Zhang
Metal nanoparticles have attracted a great deal of interest due to their unique properties of surface plasmon resonance. Metal nanoparticles can enhance the fluorescence emission intensity of quantum dots (QDs) through the local surface plasmon resonance effect, which is mainly determined by the distance between them. Therefore, it is very important to achieve controllable distance between metal and QDs, and study fluorescence enhancement. In this work, the controllable adjustment of the distance between metal nanoparticles and QDs was successfully realized by controlling the thickness of the SiO2shell of Ag@SiO2nanoparticles. Firstly, Ag nanoparticles with uniform size distribution and relatively high concentration were prepared, and then the thickness of the SiO2shell was controlled by controlling the amount of tetra-ethyl orthosilicate (TEOS) in the hydrolysis of TEOS reaction. (3-aminopropyl) triethoxysilane (APS) was used to connect CdS/ZnS QDs with Ag@SiO2nanoparticles to form Ag@SiO2@CdS/ZnS QD composite nanoparticles. The fluorescence spectra shows that the fluorescence intensity of the Ag@SiO2@CdS/ZnS QD composite nanoparticles is significantly enhanced. Photoexcitation spectra and fluorescence spectra of CdS/ZnS QD and Ag@SiO2@CdS/ZnS QD composite nanoparticles, measured under different energy excitation conditions, indicate that the existence of Ag nanoparticles can enhance the fluorescence intensity of CdS/ZnS QDs. Finally, a further physical mechanism of fluorescence enhancement is revealed.Keywords:Ag-SiO2;fluorescence enhancement;transmission electron microscope;quantum dots;photoexcitation spectra
研究领域:
材料科学
·
光学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
·
2022
·
IF 11.322
Xiaoyang Wang,Xiaoqing Si,Mingshen Li,Qihan Zhou,Jianwei Gao,Chun Li,Junlei Qi,Jian Cao
Y 2 W 3 O 12 particles with negative thermal expansion (NTE) can offset the high thermal expansion of Ag-based sealants, thus relieving the residual stress of electrolyte/interconnect joints in protonic ceramic fuel cell (PCFC) stacks. Nevertheless, violent interfacial reactions between Y 2 W 3 O 12 particles and BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ electrolyte have severely restricted the application of these NTE particles. Herein, novel Y 2 W 3 O 12 @SiO 2 composite particles with a core-shell structure are successfully designed to address this conundrum. The thermal expansion coefficient of Ag-based sealant is lowered from 19.7 to 14.6 ppm/K by adding 20 wt% Y 2 W 3 O 12 @SiO 2 particles. During joining, the SiO 2 shell significantly reduces the reaction consumption of Y 2 W 3 O 12 , fully exploiting its NTE properties. Meanwhile, a tiny portion of SiO 2 participates in and regulates interfacial reactions, generating mechanically matched reaction layers. Finite element simulation demonstrates that introducing Y 2 W 3 O 12 @SiO 2 particles significantly releases the compressive X-stress near the BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ interface, thus increasing the joint strength from ∼25.3 to ∼32.4 MPa. Obtained joints maintain long-term stability in oxidizing and reducing atmospheres at 600 °C, suggesting the applicability of Y 2 W 3 O 12 @SiO 2 composite particles in fabricating PCFC stacks. Our work provides a new strategy for preparing NTE materials with controllable interfacial reactions and service capability under extreme conditions.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）