JOURNAL OF APPLIED POLYMER SCIENCE
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2019
·Vol. 136
·期 32
·47834
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IF 2.188
Jianjun Chen,Zien Fu,Hengchao Huang,Zhonghua Chen,Xingrong Zeng
A facile route was introduced to prepare homogeneous silicone resin doped with titanium hybrid with high refractive index (RI). Specifically, the hybrids were obtained from the transesterification of hydroxyl-phenyl-vinyl silicone resin and titanium isopropoxide under anhydrous conditions. The structures of hybrid silicone and their corresponding intermediates (hydroxyl-phenyl-vinyl silicone) were characterized by nuclear magnetic resonance spectroscopy ( 1 H NMR, 29 Si NMR) as well as Fourier transform infrared spectroscopy (FTIR). The hybrids had a transmittance of more than 88% ranging from 450 nm to 800 nm, a high RI of 1.585, and a lower water vapor permeability of 3.58 g /m 2 .24h. Results from FTIR showed intensity of Ti-O-Si bond in hybrid decrease with extended the storage time, but the properties of cured hybrids including optical, mechanical, and gas permeability were not influenced. Compared to chips encapsulated with pure silicone, the luminous efficiency of the chips encapsulated with hybrids was improved from 138.6 lm/W to 156.4 lm/W. The thermal shock and hygrothermal aging test also demonstrated the hybrids had a wide range application in light-emitting diode (LED) packaging. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47834.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Yishuai Pan,Zepeng Rao,Wanchao Yu,Baoliang Chen,Chiheng Chu
Increasing worldwide contamination with organic chemical compounds is a paramount environmental challenge facing humanity. Once they enter nature, pollutants undergo transformative processes that critically shape their environmental impacts and associated risks. This research unveils previously overlooked yet widespread pathways for the transformations of organic pollutants triggered by water vapor condensation, leading to spontaneous oxidation and hydrolysis of organic pollutants. These transformations exhibit variability through either sequential or parallel hydrolysis and oxidation, contingent upon the functional groups within the organic pollutants. For instance, acetylsalicylic acid on the goethite surface underwent sequential hydrolysis and oxidation that first hydrolyzed to salicylic acid followed by hydroxylation oxidation of the benzene moiety driven by the hydroxyl radical (•OH). In contrast, chloramphenicol underwent parallel oxidation and hydrolysis, forming hydroxylated chloramphenicol and 2-amino-1-(4-nitrophenyl)-1,3-propanediol, respectively. The spontaneous oxidation and hydrolysis occurred consistently on three naturally abundant iron minerals with the key factors being •OH production capacity and surface binding strength. Given the widespread presence of iron minerals on Earth’s surface, these spontaneous transformation paths could play a role in the fate and risks of organic pollutants of health concerns.
研究领域:
环境科学
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化学
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产品关联
DOI
PubMed
高影响因子
PHYSICS OF FLUIDS
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2024
·Vol. 36
·期 6
·
IF 4.1
Hu Jun,Zhao Haonan,Xu Zhen,Hong He,Wang Zhan-Long
Anti-condensation is important in various fields, e.g., transportation, power transmission, internal drying of precision instruments. Vapor sink is an important manner to suppress the happening of water vapor condensation, and shows potentials in some special scenarios. However, the mechanism of anti-condensation by vapor sink is not well understood up until now. In this article, the effect of substrate temperature on the dry zone generated by vapor sink were systematically studied with experiments and theoretical analysis. First, the effect of hygroscopic solutions on the local humidity were measured. The results indicated that the local humidity level near the hygroscopic solutions was effectively suppressed, reducing the water vapor condensation. Second, the variation of the dry zone with the cooling substrate temperature was systematically studied. The results indicated that the dry zone exhibits a hyperbolic relationship with the substrate temperature. The dry zone changing under different humidity conditions and cooling time were also studied. The dry zone remained approximately unchanged over time in a short period. Finally, a simple yet effective model between the dry zone and substrate temperature was deduced. The theoretical results are in good agreement with the experimental data. Our study may deeper the understanding of condensation suppression via vapor sink and offer guidance to the design of anti-condensation or anti-icing surfaces.
研究领域:
工程热物理
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材料科学
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DOI
高影响因子
Nano Energy
·
2024
·
IF 16.8
Lu Huang,Peng Liu,Chenglong Qin,Chengxiang Gui,Xiantao Zhang,Tingting Ren,Yanlin Ge,Yingni Yu,Zhichun Liu,Lingen Chen
Photocatalytic hydrogen production by water splitting is considered one of the most promising green hydrogen manufacturing technologies , but the actual outdoor deployment of this technology is limited by the availability of water feedstocks in geographical locations. An integrated device consisting of a photocatalytic layer and an atmospheric water harvesting material that can achieve in-situ photocatalytic water vapor splitting for hydrogen production by spontaneously capturing moisture from the air as a water feedstock is proposed herein. The integrated system has excellent photocatalytic and photothermal synergistic ability, low hydrogen diffusion resistance by interfacial photocatalysis , and high stability by isolating salts contamination. The system can achieve a hydrogen production rate of 425.4 μmol g −1 h −1 and a water vapor supply rate of 0.121 kg m −2 h −1 under one sun illumination , and has a water vapor adsorption rate of 0.03 kg m −2 h −1 under dark conditions in the laboratory. Furthermore, this hybrid device obtains a total hydrogen production of up to 3963.1 μmol g −1 in the real outdoor daytime and accomplishes water regeneration within 10 hours by capturing environmental moisture at night. This work provides a suitable solution for hydrogen production in areas with water scarcity or drought.
研究领域:
材料科学
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能源技术
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
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IF 8.4
Zhiguang Zhang,Xiaolong Ren,Guolong Huo,Xiaowei Zhou,Hao Chen,Hongjun Zhang,Shuanyan Kang,Xiuling Chen,Nanwen Li
6FDA-based polyimide air-dehumidification membrane has been considered as one of the most advanced technologies for the energy-saving heating, ventilation, and air-conditioning systems due to their excellent solubility and processing. Nevertheless, there are few reports about the effect of free volume and hydrophilic groups on dehumidification performance. Herein, we propose to tune the free volume and hydrophilicity of 6FDA-based polyimides by tuning the hydrophilicity/hydrophobicity of diamines and/or introducing of hydrophilic carboxylic acid groups, and thus to develop a system that would support high H 2 O/N 2 separation performance for dehumidification and retain excellent mechanical properties. It is found that 6FDA/mPDA membrane shows much higher H 2 O/N 2 separation performance (i.e., H 2 O permeability 12480 Barrer and H 2 O/N 2 separation factor of 13867) than that of the 6FDA/TFDB and 6FDA/DAM membranes even though its lower FFV. It is suggested that the FFV had a negligible effect on the H 2 O/N 2 separation performance. Although the introduction of highly hydrophilic –COOH groups could significantly increase the H 2 O/N 2 separation performance of hydrophobic 6FDA/TFMB and 6FDA/DAM membranes, the performance is still lower than that of 6FDA/mPDA membrane with similar hydrophilicity. In addition, we found that more –COOH groups to polymers can lead to the possible formation of hydrophilic/hydrophobic separation in membrane which will result in the rapid water vapor condensation and thus unstable air-dehumidification. Thus, the excessive hydrophilicity of 6FDA/mPDA-DABA showed a decreased H 2 O/N 2 separation performance compared with 6FDA/mPDA membrane. These results indicated that the excellent H 2 O/N 2 separation performance mainly depends on reasonable hydrophilicity of polyimide membrane without excessive hydrophilic groups and high FFV.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
Nano Energy
·
2020
·
IF 16.602
Dunren He,Yaocheng Yang,Yuan Zhou,Juanyong Wan,Heao Wang,Xi Fan,Qi Li,Huihui Huang
Hydroelectricity is an emerging novel electricity generation phenomenon that the hydrogen bond energy is converted into chemical potential energy as electric power source by absorbing moisture. Here we report a high-performance water vapour energy harvester based on flexible MoS 2 nanosheets with a phase gradient from 1T to 2H. The phase-engineered MoS 2 film could provide open-circuit voltage and short-circuit current output of 19 mV and 6.24 µA with a low internal resistance of 3 kΩ. Additionally, the underlying mechanism of electricity generation from phase-engineered MoS 2 films was proposed in terms of contrast experiments and the plane wave density functional theory (DFT). Because of the advantages like flexible, safe, light weight and ease of scale production, this novel hydrovoltaic device could be designed as self-powered human-breathing monitor that can be integrated in disposable masks. The output voltage can be further enhanced to power commercial electronic devices by the serial connections of phase-engineered MoS 2 sponges.
研究领域:
材料科学
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能源技术
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理论物理
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2022
·
IF 7.139
Zhihua Gao,Fengyan Fu,Zhaozhi Zhang,Lili Niu,Min Jin,Jian Zhang,Zekun Zhao
Support materials are indispensable to promote the durability of iron oxides for chemical looping applications. However, the dilution effect of supports on the active phase would lead to decreased bulk oxygen conduction, thus leading to compromised activity. Here, we propose several Gd 3+ , La 3+ and Nd 3+ doped CeO 2 as active supports for iron oxides and investigate the support effect to improve hydrogen generation via chemical looping water gas shift . The characterizations show that the dopants improve the oxygen vacancy concentration in the CeO 2 lattice and Fe 2 O 3 /Ce 0.8 Gd 0.1 La 0.1 O 2-δ exhibits the most oxygen vacancy concentration among all the oxygen carriers. Pulse reactions of oxygen carriers show that an abundance of oxygen vacancy concentration can promote the lattice oxygen transfer in bulk, thus contributing to improved redox reactions . The high oxygen conductivity mitigates the dilution effect on the active phase. Therefore, Fe 2 O 3 /Ce 0.8 Gd 0.1 La 0.1 O 2-δ shows the highest hydrogen yield (∼9.49 mmol −1 .g −1 ) and hydrogen generation rate (∼0.632 mmol.g −1 .min −1 ) with only a slight decrease at 650 °C over 100 cycles. Overall, this work highlights the influence of support properties on the redox reactivity of iron oxides for chemical looping applications.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Xianfeng Peng,Jingjing Wang,Wenyan Yan,Xingyu Lin
Plant transpiration is a ubiquitous process that continuously release water vapor to the atmosphere, which is an untapped resource of water. Hygroscopic sorbents are potential candidates to address water scarcity through efficient solar-driven atmospheric water harvesting (AWH). However, the composite sorbents containing multiple components are typically toxic and environment harmful, with low photothermal efficiency and poor cyclic stability. Herein, we utilize all natural plant-derived precursors for one-step synthesis of phosphate-polymer-wrapped carbon dots (PWCD) with multi-carbonized cores inside and wrapped polymer chains in the surrounding. Without need to combine other materials, the single all-in-one PWCD particle exhibits multiple functions including low toxicity, biocompatible, high moisture absorption, low-energy desorption, high photothermal temperature, excellent cyclic stability and antibacterial properties. The PWCD can absorb water vapor across a wide range from 10% to 90% RH, with water uptake ranging from 0.11 to 3.23 g water /g absorbents . Furthermore, PWCD also shows excellent photothermal desorption ability, with final photothermal temperature surpass 100 °C for in situ sterilization. The presence of wrapped polymer prevents PWCD from aggregation and agglomeration, enhancing their cyclic stability. As the results, the biocompatible PWCD was successfully applied for water harvest from plant transpiration, producing 0.51 g·g −1 per cycle near Epipremnum aureum while keeping plant fresh.
研究领域:
材料科学
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环境科学
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植物学
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DOI
高影响因子
Small
·
2022
·Vol. 18
·期 49
·2204484
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IF 15.153
Yibo Chen,Zhi-Han Zuo,Zhao-Qing Liu,Yadong Yin
Drop-casting manganese oxide (MnO 2 ) hollow nanospheres synthesized via a simple surface-initiated redox route produces thin films exhibiting angle-independent structural colors. The colors can rapidly change in response to high-humidity dynamic water vapor (relative humidity > 90%) with excellent reversibility. When the film is triggered by dynamic water vapor with a relative humidity of ≈100%, the color changes with an optimal wavelength redshift of ≈60 nm at ≈600 ms while there is no shift under static water vapor. The unique selective response originates from the nanoscale porosity formed in the shells by randomly stacked MnO 2 nanosheets, which enhances the capillary condensation of dynamic water vapor and promotes the change of their effective refractive index for rapid color switching. The repeated color-switching tests over 100 times confirm the durability and reversibility of the MnO 2 film. The potential of these films for applications in anti-counterfeiting and information encryption is further demonstrated by reversible encoding and decoding initiated exclusively by exposure to human breath.
研究领域:
材料科学
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纳米技术
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光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2019
·
IF 3.021
Chenxu Li,Yue Zhao,Shufeng Shen
Potassium lysinate (LysK) has shown the advantages of reaction kinetics and absorption performance over conventional monoethanolamine (MEA) for CO2 capture. However, very little information is available about its desorption behaviors. In this work, CO2 solubility in aqueous 17.6, 33.5, and 40.8 mass % LysK was measured in an equilibrium reactor at temperatures of (363–393) K and CO2 partial pressures ranging from (2 to 400) kPa. Thermal degradation in the presence of CO2 and relative regeneration energy consumption for this absorbent were evaluated, and also compared with aqueous 30% MEA. An empirical model was proposed to correlate the solubility data and the calculated which are in good agreement with the experimental values with AARDs within 12%. CO2 desorption can be enhanced by overhead reflux of condensate water as a result of solvent vapor effect, which also results in the increasing evaporation heat. The aqueous LysK system was found to be less competitive than the MEA system in overall energy consumption of regeneration (kJ/mol CO2 released). Degradation of CO2-loaded LysK solutions in sealed reactors at 383 and 423 K for 5 and 15 days was qualitatively analyzed by total alkalinity and NMR spectroscopy. Compared with other absorbents, LysK has shown better resistance to thermal degradation in the presence of CO2.
研究领域:
化学工程
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环境科学
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能源技术
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气体分离
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吸收材料
✓ 已验证
DOI
高影响因子
CHEMICAL PHYSICS LETTERS
·
2023
·
IF 2.8
Tieyan Li,Hang Yu,Jianguo Mi,Chunxi Li,Hong Meng,Junsu Jin
In this study, we prepared spherical MIL-160/PAA-NH 2 composites with high atmospheric water harvesting properties by dispersing MIL-160 in a highly hydrophilic porous polyacrylate (PAA-NH 2 ) matrix by in situ growth method. The effect of MOF loading on the crystal morphology, pore structure, and vapor adsorption/desorption properties was systematically investigated. The MOF loading of the composites can be as high as 65 wt%, along with a high water vapor adsorption capacity of 0.252 g/g at 15% of relative humidity, and can provide complete desorption under mild conditions. This work provides a new idea for efficient water harvesting at low humidity.
研究领域:
材料科学
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环境科学
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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
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环境工程
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DOI
高影响因子
危险品化学品经营许可证（带存储）