Crystals
·
2021
·Vol. 11
·期 11
·1383
·
IF 2.589
Panpan Zhang,Lize Zhang,Ke Zhang,Jiupeng Zhao,Yao Li
Due to the high value of its dielectric constant, polyimide does not meet the requirements of the development of integrated circuits and high-frequency printed circuits. The development of novel low dielectric constant polyimide materials for the preparation of flexible copper clad laminates is of theoretical and practical significance in the application of polyimide for 5G communications. In this work, different fluorinated graphene/polyamic acids (FG/PAA) were used as the precursor, and the porous polyimide film was successfully prepared by phase inversion. The dielectric constant of the porous polyimide film is relatively low, being less than 1.7. When the content of fluorinated graphene is 0.5 wt%, the overall dielectric performance of the porous film is the best, with a dielectric constant of 1.56 (10 kHz) and a characteristic breakdown field strength of 56.39 kV/mm. In addition, the mechanical properties of the film are relatively poor, with tensile strengths of 13.87 MPa (0.2 wt%), 13.61 MPa (0.5 wt%), and 6.25 MPa (1.0 wt%), respectively. Therefore, further improving the breakdown resistance and mechanical properties of the porous film is essential for the application of porous ultra-low dielectric polyimide materials.Keywords:polyimide;phase inversion;dielectric constant;porous films
研究领域:
材料科学
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电子工程
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高影响因子
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
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2025
·
IF 4.7
Xueying Sun,Lina Xie,Wenlong Huo,Kaifeng Lin,Yulin Yang,Xuhui Chi,Chengyuan Zhao,Fengtao Zhang,Junzhuo Li,Debin Xia,Jian Zhang
In this study, an organic molecular probe containing an imine (C=N) linkage was synthesized and embedded in a polymethylmethacrylate (PMMA)/polyethylene glycol (PEG) matrix to fabricate a porous optical film for NO 2 gas detection via solid-state UV spectroscopy. Upon exposure to NO 2 , the film exhibited significant spectral changes, with a detection limit as low as 26.45 ppm. Mechanistic investigations revealed that NO 2 induced non-covalent interactions with the probe, triggering structural reorganization and enhanced π-conjugation. Density Functional Theory (DFT) calculations further supported these findings by confirming changes in electronic structure and energy levels. Additionally, preliminary tests demonstrated the feasibility of applying this probe film for aging detection of NEPE propellants, offering a promising non-destructive approach for monitoring propellant health.
研究领域:
材料科学
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化学
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环境监测
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2025
·
IF 2.5
Lu Wang,Lijuan Wang,Ziyang Cui,Yiqun Zhang
In order to achieve high sensitivity in gas-sensors based on organic field-effect transistors (OFETs), the most crucial and direct approach to enhance their sensing performance and reduce response and recovery times was through appropriate modification or improvement of the organic semiconductor (OSCs) layer, such as altering its surface morphology or structure. The micro/nano structure of spin-coated copper phthalocyanine (CuPc) films was controlled by utilizing polyvinyl alcohol ordered nanofibers (PVA ONFs). The electrical and gas-sensitive properties of CuPc/PVA ONFs films were investigated and analyzed. The CuPc/PVA ONFs film transistors exhibited improved output and transfer characteristics when the CuPc solution concentration was 75 mg/mL, with a mobility (μ) of 6.90 × 10-4 cm2/Vs. Compared with the spin-coated CuPc film transistors, the mobility increased by 74.24%. The sensors demonstrated the relative response of 12,942 % to 20 ppm NO2 gas. Additionally, it showed the response time of 1.49 min and recovery time of 2.32 min. The response rate reached up to 90 %, while the sensitivity was measured at 611 %/ppm, and the limit of detection (LOD) stood at 0.2 ppm. The research presented in this paper advances the potential applications of phthalocyanine materials within the realm of flexible and 3D-printed sensing technologies.
研究领域:
材料科学
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传感器技术
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电子工程
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DOI
高影响因子
MICROCHIMICA ACTA
·
2014
·Vol. 181
·期 5
·565-572
·
IF 3.719
Ma Ming,Tu Xiaojing,Zhan Guoqing,Li Chunya,Zhang Shenghui
The ionic liquid 1-butyl -3-[3-(N-pyrrole)-propyl]imidazolium tetrafluoroborate was employed to fabricate a glassy carbon electrode (GCE) modified with a porous film of a polymerized ionic liquid. The resulting film electrode was treated with sodium dodecyl sulfonate solution to exchange the terafluoroborate anions by dodecyl sulfonate groups. This was confirmed by X-ray photoelectron spectroscopy. The morphology of the modified GCE was characterized by scanning electron microscopy and revealed a nanoporous surface. The electrochemical properties of this film electrode were studied by electrochemical impedance spectroscopy using the hexacyanoferrate(II/III) system as an electroactive probe. The response to bisphenol A was investigated by voltammetry. Compared to the unmodified GCE, the oxidation potential is positively shifted, and the oxidation peak current is strongly increased. Experimental conditions were optimized and resulted in an oxidation peak current that is linearly related to concentration of bisphenol A in the 10 nM to ~ 10 μM range. The detection limit is 8.0 nM (at S / N = 3). The electrode was successfully applied to the determination of bisphenol A in leachates of plastic drinking bottles, and its accuracy was verified by independent assays via HPLC.
A poly{1 -butyl -3 -[3 -(N -pyrrole)propyl] imidazolium dodecyl sulfonate ionic liquid} nanoprous film electrode was fabricated with potential step technique and anionic exchange. The obtained polymerized ionic liquid film electrode was demonstrated possessing enhanced effects for bisphenol A determination.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
CHEMICAL PHYSICS
·
2019
·
IF 1.822
Tong-Tong Zhang,Xiang-Dong Gao,Yong-Qing Wu,Jing-Nan Yang,Xiao-Min Li
Cr-doped BaSnO 3 (BaSn 1-x Cr x O 3 , BSCO-x, x = 0–0.15) thin films with nanoporous structure were deposited on fluorine-doped tin oxide substrates via a colloidal solution route. The BSCO-x films exhibited single cubic perovskite phase and nanoporous feature, with the typical specific surface area of 18.98 m 2 /g and pore size of 10.75 nm (BSCO-0.15). The lowest band gap of 2.68 eV and a high transparency (above 70% in 500–800 nm) were realized in BSCO-0.15 film. This work paves a way toward perovskites with tunable band gap and nanoporous structures for varied photo and photoelectric devices.
研究领域:
材料科学
·
光电子学
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DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2015
·
IF 2.515
Li-Ping Wang,Ke-Yang Yin,Guang Li,Qian Liu,Ai-Xia Deng,Hui-Yan Ma
Two types of star polystyrene (SPS) were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization: three-arm star polystyrene (TSPS) and five-arm star polystyrene (FSPS). Honeycomb-structured porous films were fabricated by drop-casting of the SPS solutions on glass substrates . The regular honeycomb-patterned porous films were successfully constructed from the SPS solution casting process , and the pore diameter increased with the molecular weight of the SPS enhanced at appropriate molecular weight range. Furthermore, rhodamine B (RhB) was loaded into SPS to endow the microporous film with fluorescence. The RhB-loaded SPS film exhibits a strong and uniform red emission image.
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
JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A
·
2020
·Vol. 108
·期 8
·1713-1725
·
IF 3.525
Qing Li,Limei Li,Mali Yu,Meng Zheng,Yao Li,Jian Yang,Min Dai,Lianmei Zhong,Lin Sun,Di Lu
The extracellular matrix provides cells with a support structure and an attachment site in actual substrate. Its biochemical and surface properties play an important role in and have significant impact on cell attachment, proliferation, migration, differentiation, and gene expression. Leveraging the hydrophilicity and neuroprotective of gastrodin, a gastrodin/polyurethane (PU) elastomer was developed utilizing in situ polymerization and salt-leaching methods. The results showed that gastrodin/PU film had a good flexibility and supporting strength, as well as hydrophilicity. Thus film possessed highly surface area, interconnected porous structure with a pore size (10~60 μm) for cell attachment, and could provide surface cues to augment neurite extension. For PC12 cells cultured within the films, especially the 5gastrodin/PU group, presented a progressive increase with time, coupled with the upregulation of brain-derived neurotrophic factor and glial cell derived neurotrophic factor expression. This is the first report on the construction of a gastrodin/PU porous film, and the results reveal its promise as a scaffold material for neural tissue engineering.
研究领域:
生物材料学
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神经科学
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组织工程学
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DOI
PubMed
高影响因子
Small
·
2022
·Vol. 18
·期 28
·2202651
·
IF 15.153
Shuanglin Wu,Yingmei Yao,Xiaolin Nie,Zhifeng Yu,Yanting Yu,Fenglin Huang
Exploring a scalable strategy to fabricate a multifunctional separator is of great significance to overcome the challenges of lithium polysulfides (LiPSs) and dendritic growth in lithium-sulfur batteries (LSBs). Herein, a binder-free Janus separator is constructed by interfacial engineering. At the cathode interface, an ultra-thin covalent triazine piperazine film containing tailorable micropores and adsorption sites is decorated on polyacrylonitrile (PAN) membrane by in situ interfacial polymerization, building a triple barrier for LiPSs. The combination of steric hindrance and chemical adsorption reduces LiPS's migration by 81.85%. Meanwhile, at the anode interface, a fast-ionic conductor Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) is created on the surface of PAN nanofiber by magnetron sputtering to suppress dendrite growth. Even though there is no binder between the ceramic layer and the fibrous separator, sputtering creates an inter-embedded structure that ensures no depowering after cycling. Furthermore, the PAN-based separator displays a high temperature tolerance of 180 °C. Consequently, the cell delivers a high capacity of 1287.9 mAh g −1 at 0.5 C and stable cycling performance with an ultra-low capacity decay rate of 0.059% per cycle over 500 cycles. This work provides a scalable strategy for functionalizing separators to tackle the challenges in LSBs, which is binder-free, stripping-free, and essentially thickening-free.
研究领域:
材料科学
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能源存储技术
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Qianzhi Chen,Yuxuan Liu,Anli Yi,Zhongyan Man,Rui Jiao,Hanxue Sun,Jiyan Li,An Li
The interfacial solar steam generation for seawater desalination has attracted attention because of its excellent photothermal performance and efficiency. However, the process of preparing evaporators is often complex and costly, which limits their further practicality. Here, we report an integrated solar evaporator that is easy to prepare and has good salt resistance. The porous structure of poly(methyl methacrylate) and polycarbonate (PMMA–PC) films prepared by the breathing figure (BF) method was used as the upper layer, while MXene was deposited on the as-resulted PMMA–PC film and served as a light absorption layer. Meanwhile, the hydrophilicity of the lower layer of expanded polyethylene (EPE) foam can promote the upward transfer of water and inhibit heat loss. Under one solar irradiation, the water evaporation rate of the composite film was found to be 1.79 kg m–2 h–1 in distilled water and 1.67 kg m–2 h–1 in a 15 wt % NaCl solution, exhibiting excellent evaporation performance and salt resistance. In addition, the PMMA–PC/MXene films exhibit excellent mechanical properties. Based on these merits of the PMMA–PC/MXene solar generator, it may find useful applications in practical solar interfacial evaporation. Moreover, the findings of this investigation may provide a new opportunity for the rational design of large-aperture photothermal conversion materials via a simple breathing figure method.
研究领域:
材料科学
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能源科学
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DOI
PubMed
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2013
·
IF 2.072
Wenkai Chang,Fujian Xu,Xueyan Mu,Lili Ji,Guiping Ma,Kemin Wang,Jun Nie
Titanium dioxide (TiO 2 ) thin films with porous structures have been successfully achieved by photopolymerization stimulating the particle dispersion combined TiO 2 colloid with photoinitiator and monomer. The photopolymerization monomer Pentaerythritol Triacrylate (PETA) and photoinitiator 2-Hydroxy-2-methyl-propiophenone (HMPP) are added to the TiO 2 colloidal solution to form the new colloidal TiO 2 dispersion. After coating the dispersion on the substrate, the coating is cured with UV light. With the evaporation of solvent and the formation of microgels induced by polymerization, a phase separation occurs in the system. A porous TiO 2 film with various pore sizes from mesoporous to macroporous could be produced after heat treatment. The morphology and size of pores could be tuned by changing the process of phase separation, which is controlled by the composition of colloidal TiO 2 dispersion. The content of photoinitiator and the temperature of heat treatment were decided by UV–vis absorption spectra and thermal analysis (DTA–TGA), respectively; Real-Time Fourier-transform infrared (RT-FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffractometer (XRD) and high-resolution transmission electron microscopy (HR-TEM) were used to characterize the TiO 2 films. The as-prepared TiO 2 porous films exhibited higher photocatalytic activity for degradation methylene blue in comparison with conventional TiO 2 dense film due to its porous structure.
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
MATERIALS LETTERS
·
2013
·
IF 2.224
Chun-Xia Liu,Wan-Zhong Lang,Bin-Bin Shi,Ya-Jun Guo
In this research, the ordered honeycomb-patterned polyvinyl chloride (PVC) porous films were first fabricated with hydrophilic tetrahydrofurane (THF) as a solvent by the “Breath figures” (BFs) method. The effects of polymer concentration, polymerization degree of PVC, and air humidity on the formation of PVC films were investigated. The experimental results indicate that the increase of polymer concentration leads to the decrease of the hole size of the resultant films, and even makes the porous structure disappear. Besides, the porous films can be easily fabricated with higher polymerization degree of PVC at 40 mg mL −1 . Increasing air humidity is advantageous to form well-ordered porous PVC films with larger hole size.
研究领域:
材料科学
·
高分子化学
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DOI
高影响因子
LANGMUIR
·
2024
·
IF 3.7
Zhenghao Shi,Yifeng Sheng,Jianhui Wu,Jiwei Cui,Wei Lin,To Ngai
Waterborne polyurethane (WPU) latex nanoparticles with proven interfacial activity were utilized to stabilize air–water interfaces of Pickering foams through interfacial interaction with hydrophobic fumed silica particles (SPs). The rheological properties of the Pickering foam were tailored through adjustment of their SP content, which influenced their formability and stability. A Pickering foam stabilized with WPU and SPs was used as a template to prepare a WPU–SP composite porous film. The as-prepared film had intact open-cell porous structures, which increased its water absorption and water-vapor permeability. The porous film was used as a middle layer in the preparation of synthetic leather via a four-step “drying method”. Compared with commercial synthetic leather, the lab-made synthetic leather with a middle layer made of the WPU–SP composite porous film exhibited a richer porous structure, acceptable wetting on a fabric substrate, a thicker porous layer, and higher water-vapor permeability. This work provides a novel and facile approach for preparing WPU–SP Pickering foams. Furthermore, the foams have the potential to function as a sustainable material for creating a porous-structured synthetic leather made from WPU, which may be utilized as an alternative to solvent-based synthetic leather.
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
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