MOLECULES
·
2024
·Vol. 29
·期 20
·4794
·
IF 4.2
Lin Lin,Ziqi Li,Jian Zhang,Tonghua Ma,Renzhong Wei,Qiang Zhang,Junyou Shi
Phase change energy storage microcapsules were synthesized in situ by using melamine-formaldehyde–urea co-condensation resin (MUF) as wall material, n-octadecane (C18) as core material and styryl-maleic anhydride copolymer (SMA) as emulsifier. Fourier transform infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry and thermogravimetric analysis were used to study the effects of emulsifier type, emulsifier dosage, core–wall ratio and pH on the morphology and thermal properties of microcapsules. The results show that the pH of core material and the ratio of core to wall have a great influence on the performance of microcapsules. SMA emulsifiers and MUF are suitable for the encapsulation of C18. When the pH is 4.5 and the core–wall ratio is 2/1, the latent heat and encapsulation efficiency of phase transition reaches 207.3 J g−1and 84.7%, respectively. The prepared phase-change microcapsules also have good shape stability and thermal stability.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
KEY ENGINEERING MATERIALS
·
2016
·
IF 0
Yan Yang Yang,Hao Wang,Guo Lin Song,Guo Yi Tang
Phase change method is one of the efficient approach in resolving energy problem for solar energy storage. However, phase change materials seriously affect the heat storage system with low heat releasing and absorbing rate for poor thermal conductivity performance, which result in an inefficient thermal energy storage technology and uncertain economic perspective. In this paper, we prepared dual-functional phase change nanocapsules based on n-octadecane core and polypyrrole shell. Polypyrrole was employed to enhance the electric conductivity and thermal conductivity. The nanocapsules was characterized using Fourier transformed infrared spectrophotometer (FTIR), field emission scanning electron microscope (FESEM), differential scanning calorimeter (DSC), thermal gravimetric analyzer (TGA) and infrared thermal imaging. The results shows a good thermal behavior and high latent heat of 81.99J/g. The dual-fuctional phase change nanocapsules can be expected with a prospect of future profits in energy storage technology.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
Scientific Reports
·
2017
·Vol. 7
·期 1
·1-9
·
IF 4.259
Liu Eryong,Li Longyang,Wang Gang,Zeng Zhixiang,Zhao Wenjie,Xue Qunji
Compliant fish skin is effectively in reducing drag, thus the design and application of compliant bionic materials may be a good choice for drag reduction. Here we consider the drag reduction of compliant bionic materials. First, ZnO and PDMS mesh modified with n-octadecane were prepared, the drag reduction of self-texturing compliant n-octadecane were studied. The results show that the mesh modified by ZnO and PDMS possess excellent lipophilic and hydrophobic, thus n-octadecane at solid, semisolid and liquid state all have good adhesion with modified mesh. The states of n-octadecane changed with temperature, thus, the surface contact angle and adhesive force all varies obviously at different state. The contact angle decreases with temperature, the adhesive force shows a lower value at semisolid state. Furthermore, the drag testing results show that the compliant n-octadecane film is more effectively in drag reduction than superhydrophobic ZnO/PDMS film, indicating that the drag reduction mechanism of n-octadecane is significantly different with superhydrophobic film. Further research shows that the water flow leads to self-texturing of semisolid state n-octadecane, which is similar with compliant fish skin. Therefore, the compliant bionic materials of semisolid state n-octadecane with regular bulge plays a major role in the drag reduction.
研究领域:
生物力学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advances in Civil Engineering
·
2019
·
IF 1.104
Jianping Zhu,Benkai Guo,Huanhuan Hou,Wenyan Zhang
Phase change materials (PCMs) have been widely used to improve the thermal energy storage capacity of building materials. In this study, the n-octadecane (OD)/expanded perlite (EP) composite PCM, which was prepared by incorporation of liquid n-octadecane into EP using the vacuum impregnation method, was used to fabricate the gypsum board. The microscopic, thermal, and mechanical properties were studied. The SEM results showed that OD could be absorbed into the pores of EP uniformly. The FI-IR results showed that OD and EP have good chemical stability. It was found that the gypsum board has best heat transfer delay when the volume fraction of OD/EP was 20% (v/v). The mechanical property of the gypsum board with OD/EP decreased. To deal with the problem, the effect of nano-Al2O3 on the gypsum board was also studied. The results showed that the mechanical properties of the gypsum board were effectively increased when the dosage of nano-Al2O3 was 0.5 wt.%, and the gypsum board had the best thermal insulation effect when the nano-Al2O3 content was 0.3 wt.%. Considering the cost and the comprehensive property, it was suggested that the optimal addition content of nano-Al2O3 was 0.3 wt.%.
研究领域:
建筑材料
·
能源存储
·
复合材料
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2011
·
IF 4.746
Xiaolin Qiu,Wei Li,Guolin Song,Xiaodong Chu,Guoyi Tang
Microencapsulations of n-octadecane with different crosslinked methylmethacrylate-based polymer as shells were carried out by suspension-like polymerizations. 1,4-butylene glycol diacrylate (BDDA), divinylbenzene (DVB), trimethylolpropanetriacrylate (TMPTA) and pentaerythritol tetraacrylate (PETRA) were employed as crosslinking agents. The influences of the type and amount of crosslinking agent, the type of initiator and polymerization temperature on the properties of as-prepared microencapsulated phase change materials (MicroPCMs) have been studied. The MicroPCMs were characterized using Fourier transformed infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). Thermal properties and thermal stability of MicroPCMs were investigated by differential scanning calorimetry (DSC) and thermalgravimetric analysis (TGA). Shell mechanical strength was measured by micro/nano-hardness tester. Thermal properties, thermal resistant temperatures as well as shell mechanical strength of MicroPCMs enhanced as the number of crosslinkable functional moieties of the crosslinking agents increased. The MicroPCMs containing 75.3 wt% n-octadecane obtained using PETRA as crosslinking agent has the highest latent heats of melting (156.4 J/g) and crystallization (182.8 J/g) and displays the highest thermal stability and shell mechanical strength. The MicroPCMs prepared with DVB shows a relatively higher shell mechanical strength and heat capacity compared with those prepared with BDDA. Both heat capacity and thermal stability of MicroPCMs prepared by combining 2,2 ′ -azobisisobutyronitrile (AIBN) and redox initiators at 45 °C were lower than that of MicroPCMs prepared with AIBN or benzoyl peroxide (BPO) at 85 °C. Hence, MicroPCMs with crosslinked methylmethacrylate-based polymer as shells, especially crosslinked polymer shells of higher crosslinking density , show a good potential as a solar-energy storage material.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2021
·
IF 4.539
Chun Bai,Kexin Li,Dezhen Fang,Xiushen Ye,Huifang Zhang,Quan Li,Jun Li,Haining Liu,Zhijian Wu
A novel flotation agent named N-octadecyl-N-methyl- D -glucamine (NO-NMDG), was designed and prepared using N-methyl- D -glucamine as a polyhydroxy molecule and 1-bromooctadecane as the provider of a long-chain alkyl group . The results of characterization by NMR, MS and FT-IR showed that the target compound was successfully synthesized. NO-NMDG can effectively separate boron from aqueous solutions because of its complexing ability for boron and its foamability. The flotation experiments results showed that the flotation isotherm was in better accordance with the Langmuir model, indicating that the surface reaction in flotation by NO-NMDG belongs to the single molecular layer trapping. The response surface experimental results indicated that under the optimum conditions, the boron recovery rate can reach to 89.12%. The boron recovery rate in Xiao Chaidan brine could reach to 97.26% by NO-NMDG. The mechanism analysis exhibited that the meglumine group in NO-NMDG can complex with boron, and the long-chain alkyl group can attach to the surface of the bubble and enter into the bubble layer to separate boron from the aqueous solution.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
·
2019
·
IF 2.752
Yu Li,Liang Zhao,Hao Wang,Baohua Li
The novel microencapsulated n -octadecane with TiO 2 -doped silk fibroin (SF) shell was synthesized using a self-assembly method in o/w emulsion. It was confirmed by Fourier transformation infrared spectroscope (FT-IR) and a three-phase contact angle that TiO 2 is successfully modified by SF aqueous solution. The scanning electronic microscope (SEM) and laser scattering particle size distribution analyzer showed that the as-prepared microcapsules have regularly spherical morphology and are about 4–5 μm in average diameter. According to differential scanning calorimeter (DSC), thermogravimetric analyzer (TGA) and ultraviolet visible spectrophotometer (UV–vis) measurements, the TiO 2 -doped microcapsule presents high thermal storage capability, enhanced thermal reliability and stability, and have good UV-shielding property. The TiO 2 -doped microcapsule synthesized in the present study could prove to be path-breaking and lead to further studies in the field of thermal energy storage and UV-shielding applications.
研究领域:
材料科学
·
能源工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2017
·Vol. 7
·期 5
·96
·
IF 3.553
Xiaofeng Niu,Qing Xu,Yi Zhang,Yue Zhang,Yufeng Yan,Tao Liu
Micro-nanoencapsulated phase change materials (M-NEPCMs) are proposed to be useful in liquid desiccant dehumidification by restraining the temperature rise in the moisture-removal process and improving the dehumidification efficiency. In this paper, then-octadecane M-NEPCMs with desirable thermal properties for internally-cooled dehumidification were fabricated by using compound emulsifiers through the in-situ polymerization method. Melamine-formaldehyde resin was used as the shell material. The effects of the mixing ratio, emulsification methods and amount of the compound emulsifiers on the morphology, size and thermal properties of the M-NEPCMs were investigated experimentally. The optimum weight mixing ratio of the compound emulsifiers is SDS (sodium dodecyl sulfate):Tween80 (polyoxyethylene sorbitan monooleate):Span80 (sorbitan monooleate) = 0.1:0.6:0.3, which achieves the best stability of then-octadecane emulsion. When the compound emulsifiers are 10 wt. % of the core material, the melting enthalpy of M-NEPCMs reaches its maximum of 145.26 J/g of capsules, with an encapsulation efficiency of 62.88% and a mean diameter of 636 nm. The sub-cooling of the prepared M-NEPCMs is lower than 3 °C, with an acceptable thermal reliability after the thermal cycling test. A pre-emulsification prior to the addition of deionized water in the emulsification is beneficial to the morphology of the capsules, as the phase change enthalpy can be increased by 123.7%.Keywords:micro-nanoencapsulatedn-octadecane;phase change properties;microstructure;compound emulsifiers;liquid desiccant
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·
IF 7.139
Weilin Zhong,Chao Wang,Bo Jiang,Suqing Peng,Hailun Zhao,Riyang Shu,Zhipeng Tian,Yanping Du,Ying Chen
Combining solar energy utilization and hydrogen production is an ideal model for renewable energy development. Especially the conversion of broad-spectrum solar energy into chemical energy of hydrogen and thermal energy can enrich solar energy storage methods. Herein, novel multifunctional Au/TiO 2 @n-octadecane microcapsules with core-shell structure were design and synthesized by wet chemical reduction and electrostatic adsorption self-assembly methods for photothermal hydrogen production and thermal storage . The results showed that microencapsulation of photothermal catalysts could provide an effective reaction area and excellent dispersion stability , where hydrogen production and light to hydrogen efficiency were increased in the 43% and 0.3% respectively, compared to the nanoparticle suspension system. Based on the recorded temperature variations caused by the photothermal effect, the calculated photothermal conversion efficiency and specific absorption rate of Au/TiO 2 @n-octadecane was 25.01% and 277% higher than that of Au/TiO 2 suspension. The proposed hydrogen production and thermal storage method via multifunctional microcapsules might shed some light on the study of improving full-spectrum energy conversion efficiency of solar energy.
研究领域:
材料科学
·
能源科学
·
纳米技术
✓ 已验证
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2025
·
IF 6.3
Ruishuo Guo,Huijia Wang,Qingwen Wen,Xin Xu,Yanlan Zhou,Xiaoqiang Shao,Ni Li
Phase change capsules effectively address the limitations of leakage and poor stability of phase change materials (PCMs). In this study, SiO 2 @n-Octadecane phase change nanocapsules (PCNCs) with controllable size and structure are prepared by controlling material ratios. When Water-to-EtOH ratio is 2:1 and C 18 -to-TEOS ratio is 3:3 in the reaction system, prepared PCNCs show excellent phase change enthalpy of 152.9 J/g and high encapsulation ratio of 73.77 %, with desirable thermal stability and reliability. After the irradiation of simulating sunlight for 1500 s, the PCNCs achieved a temperature buffer of 6 °C compared with blank cotton fabric, and the cotton fabric with the PU coating containing the PCNCs presents up to 13.2 °C temperature reduction compared with original cotton fabric. The prepared SiO 2 @n-Octadecane PCNCs present excellent heat storage and thermal management performance and effective strategy to develop long-term thermal comfort smart textiles.
研究领域:
材料科学
·
纳米技术
·
热工工程
·
智能纺织
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES
·
2023
·
IF 3.5
Lei Ni,Dongyan Yang,Yinshan Liu,Chenghao Li,Qiang Chen,Juncheng Jiang,Yong Pan
Reaction thermal runaway accidents occur frequently and occupy a high proportion in chemical accidents. Reducing accidents by controlling reaction temperature is of great implication to enhance the safety level of chemical processes. Phase change materials (PCMs) have a good energy storage potential, which can rapidly convert the reaction exotherm in the reaction process into its own phase change latent heat, urgently control the reaction temperature, and enhance the process thermal safety level. In this study, using n -octadecane as the core and melamine-formaldehyde (MF) resin as the shell, microencapsulated phase change materials (microPCMs) was made, which has a smooth spherical shape, good thermal stability , and a phase change enthalpy up to 162.87 J/g. The homogeneous esterification reaction of 2-butanol (2 B) and propionic anhydride (PA) was selected as the target reaction, and then the reaction was scaled up equivalently to investigate the effect of amplification to the reaction system. The results indicated that the temperature control of the esterification reaction system by microPCMs is the synergy between physical inhibition and chemical inhibition. The reaction temperature could be controlled by adding microPCMs, and the temperature control effect improved with the increase of microPCMs addition. In large scale reactors, microPCMs still has certain temperature control ability after being added.
研究领域:
化学工程
·
材料科学
·
安全工程
✓ 已验证
产品关联
DOI
高影响因子
THERMOCHIMICA ACTA
·
2023
·
IF 3.5
Lei Liu,Runfeng Li,Min Guo,Linjun Wang,Mei Zhang
In this manuscript, CuS-ZnS/SiO 2 @n-octadecane nanocapsules were prepared by a simple one-step Cu 2+ and Zn 2+ co-deposition method. The results of XRD, SEM, TEM, FTIR and XPS show that nanocapsules composed of CuS-ZnS/SiO 2 shell and n-octadecane core material were successfully prepared, and the particles deposited was proved to be composite structure of CuS-ZnS. The solution concentration, reaction temperature and pH value have significant effects on the morphology of the nanocapsules prepared. The appropriate conditions are 0.02 mol/L CuSO 4 , 0.02 mol/L Zn(CH 3 COO) 2 , 60 °C, and no additional pH adjustment. Under the optimum conditions, the melting enthalpy reached 45.11 J/g, and after 100 times of cold and hot cycles, the melting enthalpy of the sample only decreased by 3.2%, showing good thermal stability. The CuS-ZnS composite structure makes CuS-ZnS/SiO 2 nanocapsules exhibit a wider spectrum absorption performance. The absorption effect of CuS-ZnS/SiO 2 nanocapsules to ultraviolet light is significant, compared to the slight reducing of the visible light, while the absorption of near-infrared light is strong. The photothermal conversion efficiency of the samples is significantly improved from 9.7% to 86.6%. Hence, the prepared nanocapsules achieve full spectral absorption, which has a broad application prospect in solar thermal utilization.
研究领域:
材料科学
·
能源科学
·
纳米技术
✓ 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）