PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2017
·Vol. 19
·期 35
·23898-23904
·
IF 4.123
Congdi Shang,Li Wang,Yanqin An,Ping Chen,Xingmao Chang,Yanyu Qi,Rui Kang,Yu Fang
Fast, sensitive and selective detection of diamines in the vapor phase is of pivotal importance for air and food quality monitoring. In this work, an electron-poor fluorophore, perylene bisimide (PBI), was modified with hydrophilic residues at its bay positions, resulting in an amphiphilic derivative, PEBBO. Photophysical studies revealed that the compound shows a strong aggregation tendency in various solvents, but the aggregates could be highly fluorescent provided suitable solvents are used. Accordingly, a fluorescent film was constructed via utilization of the well-known Langmuir–Blodgett technique. Sensing performance studies revealed that the film as prepared is sensitive and selective to the presence of diamines in air. Specifically, (1) the experimental detection limit is lower than 0.016 g m−3 and the linear range of the analysis extends from 0.33 g m−3 to 8.20 g m−3 when ethylenediamine was adopted as an example analyte; (2) the presence of other amines and solvents shows little effect upon detection; (3) the response time is less than 5 s. Considering the importance of diamine sensing, the convenience of fluorescence techniques and the superiorities of the film and method as developed, it is believed that the present work is of great importance for promoting technical progress in diamine sensing.
研究领域:
化学
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Xuan Guo,Jianlong Wang
The Langmuir isotherm model is widely used for modeling adsorption equilibrium data. The linearization method is mostly applied for estimations of the Langmuir parameters. However, it is not unified and requires further study. In this paper, the applicability and accuracy of four linearization methods of the Langmuir isotherm (equilibrium adsorbate concentration ( C e )/equilibrium adsorption capacity ( q e )- C e , 1/ q e -1/ C e , q e - q e / C e and q e / C e - q e ) in parameter estimations by linear least squares regression (LSR) were compared. The influence of linearization on the assumption about errors in the LSR variables was analyzed. The results showed that Langmuir-1 ( C e / q e - C e ) and Langmuir-4 ( q e / C e - q e ) followed the assumption for all evaluated conditions whereas Langmuir-3 ( q e - q e / C e ) violated the assumption for all conditions. Langmuir-2 (1/ q e -1/ C e ) obeyed the assumption of LSR only when C e approached the initial adsorbate concentration ( C 0 ). Langmuir-1 ( C e / q e - C e ) provided the most accurate estimations of the Langmuir parameters, particularly at low levels of random errors in C e and when the errors (%) in estimated maximum adsorption capacity ( q m ) and constant ( K a ) ranged from −5% to 5% and from −15% to 15% at low levels of errors (−0.5–0.5 mg/L), respectively. The Langmuir-1 isotherm model adequately represented the experimental equilibrium data of sulfamethoxazole (SMX) onto activated carbon with an R 2 value of 0.96.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
INTEGRATED FERROELECTRICS
·
2020
·
IF 0.557
Min Li,You Yang,Ran Wang,Xudong Yu,Jianmin Gu,Yandi Rao,Jingjing Su,Jinghong Li,Tifeng Jiao
Cholesterol is widely used in the field of amphiphilic self-assembly as a small organic molecular structural unit. In this article, new cholesterol amide derivative (CHAM) films via molecular self-assembly technology have been successfully prepared. Scanning electron microscope, transmission electron microscope, UV–Vis spectra, atomic force microscopy (AFM), contact angle and Fourier transform infrared spectroscopy were measured to characterize the morphology and nanostructure of the prepared self-assembled CHAM Langmuir–Blodgett (LB) films. The obtained experimental data revealed that different subphases played an important role in formation of a stable LB film, resulting in different assembly behavior. CHAM contains adamantane units and highly symmetrical tricyclic aliphatic hydrocarbon clusters, so it can combined with cyclodextrin through host–guest interact, for CHAM act as host and cyclodextrin containing a hydrophobic cavity act as guest. The morphology of single-layer Langmuir films with different subphases was characterized by AFM, indicating that the CHAM molecules formed a stable LB films on the surface of the pure water subphase, cyclodextrin subphase and cyclodextrin polymer subphase. The photoelectric properties were characterized by J-V characteristics, EIS response and impedance map, and it was found that the CHAM film had better photoelectric properties.
研究领域:
材料科学
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2015
·Vol. 162
·期 4
·H229
·
IF 3.266
Mei Huang,Xiaoli Mao,Dechao Chen,Shulian He,Shuai He,Wenhong Liu,Jinzhang Xu,Shiding Miao
A new type of Nile blue (Nb) derivative molecules terminated with long-chain alkyl (termed as Nb18) has been synthesized from precursors of barium stearate and 3-amino-7-(diethylamino)-1,2-benzophenoxazin sulfate. Optical characterizations including UV-Vis absorption, fluorescence emission, excitation spectra and the infrared spectroscopy reveal a blueshift in the band emission of Nb18 as compared to the Nb molecule, and this shift was found to be reasoned by incorporation of long-chain alkyl groups and replacement of SO42−. The amphiphilic Nb18 molecules were found to form stable Langmuir monolayers over aqueous solutions, and this allows one to study the kinetics of Nb18 formation by means of surficial chemistry. The synthetic reaction was demonstrated to have first-order kinetics with a rate constant of ∼0.0033 s−1. Using different techniques (Langmuir-Blodgett and Langmuir-Schaefer) monolayers of Nb18 were deposited on an electrode where the amphiphilic molecules were differently oriented. Investigation of these films undertaken to confirm some of the previous electrochemical observations indicated that the electro-catalytic activity stems from the cationic rings of aromatic oxazine regarding to the oxidation of dihydronicotinamide adenine dinucleotide (NADH).
研究领域:
有机化学
·
表面化学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2017
·
IF 2.714
Yagui Gao,Tifeng Jiao,Ruirui Xing,Lexin Zhang,Jingxin Zhou,Qiuming Peng
The design and preparation of functional beta-cyclodextrin-based composite films are of key importance for wide application fields. This study demonstrates a new route to construct composite films by Langmuir-Blodgett (LB) method via cholesterol-modified beta-cyclodextrin derivative (CD-CHOL). The inclusion complex formation of CD-CHOL and azobenzene derivative (N-Azo) at the air/water interface was investigated. It has been found that the interfacial host-guest recognition could easily occur in the in situ formed CD-CHOL/N-Azo composite films and relatively difficult to occur in the ex situ immersed composite films, because there exist host-guest interaction as well as intermolecular hydrogen bonding interaction. The inclusion complex formation was confirmed by changes in the surface pressure-area isotherms, circular dichroism (CD) and UV–vis spectra of the transferred LB films . And the solvent effect of the composite CD-CHOL/N-Azo films was also investigated, indicating that host-guest interaction between N-Azo and CD-CHOL could occur rather in the nonpolar solvent than the polar solvent . The present research work about beta-cyclodextrin-based composite films by LB method may provide new exploration to prepare organized composite films and demonstrate potential applications in many fields.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Ya Li,Chao-Yu Wang,Dong-Jin Qian
Molecular arrangement and orientation of tetraphenylethylene (TPE) unit in the highly ordered thin films and aggregates can effectively limit its conformation that results in strong effect on the excited energy transfer process and luminescent behaviors under irradiation. We report here an interfacial self-assembly of metal-TPE coordination polymer (CP) ultrathin films and their aggregate-induced emission (AIE) behaviors. After connected with pyridyl or benzimidazole substituents, the tetradentate TPEs as synthesized are used as the multidentate linkers to coordinate with the Cd 2+ ions to produce aggregates in the solutions, and to form well-defined two- and three-dimensional organized Cd-TPE CP multilayers at the air-water interfaces by the Langmuir-Blodgett (LB) method. It is revealed that, in addition to the aggregation-induced emission, the following external factors have also large effects on the luminescence of TPEs , including the coordination bonding in the CPs, in plane and interlayer molecular interaction in the LB films ; both of them can restrict the intramolecular motion or rotation of TPE unit. Because of these external effects, the emission lifetime of TPEs reaches to approximately 5–10 times longer in some Cd-TPE CP LB films than that in the solutions. Further, the luminescent emission wavelengths and colors of LB films can be tuned to some extent by the in-plane and interlayer molecular interaction. Finally, it is demonstrated that the luminescent emissions and colors of the Cd-TPPE CP LB films is selectively sensing to methanol and formic acid in the gas phase with good reversibility and reproductivity.
研究领域:
材料化学
·
光物理学
✓ 已验证
产品关联
DOI
高影响因子
SURFACE REVIEW AND LETTERS
·
2013
·
IF 0.276
YUDI GUO,DONGYAN TANG,SHUO GU
The dependence of particulate Langmuir–Blodgett (LB) monolayer quality on the surface nature of the substrate was investigated by pretreating the substrates with different methods, and the optimal withdrawal speed was determined by detecting the quality of particulate monolayers deposited at different withdrawal speeds. Furthermore, the effects of stearic acid (SA) concentration on the quality of particulate monolayers were discussed. Results indicated that surface amination would favor the transfer of the floating particulate monolayer from the interface to the substrate, which would be attributed to the formation of chemical bonds between the – NH 2 groups on the substrate surface and the functional groups of – COOH and Si – OH groups on surfaces of particles floating at the interface. And the withdrawal speed of 1 mm ⋅ min -1 was appropriate for the fabrication of high-quality particulate LB monolayer because low withdrawal speed can offer sufficient time to form chemical bonds and expel the subphase from the substrate. Additionally, SEM images illustrated that the SA concentration of 0.40 mg ⋅ mL -1 was suitable for the fabrication of well-ordered particulate LB monolayers composed by the particles of 380 nm.
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
RSC Advances
·
2017
·Vol. 7
·期 65
·41043-41051
·
IF 3.108
Yagui Gao,Tifeng Jiao,Kai Ma,Ruirui Xing,Lexin Zhang,Jingxin Zhou,Qiuming Peng
The preparation of graphene oxide (GO)-based composite Langmuir films play important roles in the application of self-assembly nanomaterials. In this work, beta-cyclodextrin-modified graphene oxide (GO–CD) and the azobenzene-modified PAA derivative (abbreviated as PAA-Azo) have been designed and synthesized. The interfacial assemblies and host–guest interactions of GO–CD material with used two azobenzene compounds (N-Azo and PAA-Azo) in the obtained Langmuir and Langmuir–Blodgett (LB) films were investigated. All the spreading films from different subphases were transferred onto solid substrates and their nanoscale morphologies as well as self-assembled characteristics were investigated by some methods including atomic force microscopy, UV-vis spectra, Raman spectra, etc. The obtained results indicated that there existed host–guest interaction between beta-CD segments with azobenzene groups. Besides, in the obtained GO–CD/N-Azo films, there also appeared J-aggregate of N-Azo molecules on GO sheet surface. However, there were only host–guest interactions without any aggregates of azobenzene segment in the GO–CD/PAA-Azo composite films. Hence, the presently obtained GO–CD/azobenzene composite Langmuir films provide new clues to develop GO-based self-assembled films as well as nanomaterials towards nano-device and sensor applications.
研究领域:
材料科学
·
纳米技术
·
化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2021
·
IF 4.539
Chongling Wang,Na Li,Pengfei Bian,Guohua Li,Jingyue Yang,Qing Li,Tifeng Jiao
Molecular self-assembly is a technology in which different structural components spontaneously form assemblies with special functions through weak, reversible non-covalent interactions on the basis of molecular recognition . The amphiphilic and biocompatibility of polypeptides make it has natural advantage in self-assembly at the air-water interface. In this work, the self-assembled films of palmitoyl pentapeptide-4 (PP4) and dye molecules were prepared by Langmuir-Blodgett (LB) technology. It was found that the PP4/dye composite film had good acid-alkali gas response. In addition, the LB film prepared by PP4 and methyl orange (MO) showed chiral signal, which was reflected in the circular dichroism spectrum. The current research work provides new clues for the preparation of functional self-assembled films and their applications as gas sensors and chemical switches.
研究领域:
生物化学
·
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2024
·
IF 5.7
Cong Yu,Jian Wang,Jingjing Yan,Jianlong Xia,Xin Zhang
Dielectric polymers with inherent flexibility, high breakdown strength, and low cost have garnered significant attention for their potential applications as energy storage mediums in advanced electronic and electrical systems. However, these current polymers exhibit a low dielectric constant and inferior thermal stability, resulting in a low energy density and limited operation temperature. In this work, we present a Langmuir–Blodgett (LB) technique-assisted approach for achieving a multilayered polyetherimide (PEI)/calcium niobate (CNO) nanocomposite with in-plane aligned CNO nanosheet layers embedded within the polymer matrix. The LB deposition technique enables a precise in-plane alignment and a densely packed arrangement of CNO nanosheets within the PEI matrix, thereby effectively impeding charge transfer and establishing a continuous heat-conducting network. Consequently, the multilayered PEI/CNO nanocomposite exhibits a significant reduction in leakage current density and an enhancement in breakdown strength at elevated temperatures compared to the pure PEI polymer. Additionally, the incorporation of CNO nanosheets also leads to an increase in the dielectric constant of the nanocomposites. Due to these improvements in the dielectric constant and high-temperature breakdown strength, the multilayered nanocomposite achieves a remarkable 180% enhancement in energy density compared to pure PEI, reaching 6.9 J cm−3 at 150 °C (with an energy efficiency exceeding 90%). Furthermore, the nanocomposite film-based multilayer polymer capacitor (MLPC) device exhibits exceptional capacitance and outstanding flexibility, showcasing the immense potential of these multilayered nanocomposite films in high-temperature electronic and electrical systems.
研究领域:
材料科学
·
能源存储
·
纳米复合材料
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Dongxue Han,Guohua Li,Jie Wang,Teng Zheng,Liang Peng,Lin Li,Tifeng Jiao
Self-assembly is a technique that utilizes non-covalent interactions between molecules to assemble into ordered nano-scale aggregates from disordered states. Langmuir-Blodgett (LB) technique is one of the commonly applied methods for constructing molecular assemblies at gas-liquid interfaces. In this study, a series of ordered composite films of amino-functionalized carbon nanotubes (MWCNTs-NH 2 ) and different dye molecules were prepared using LB technique. The surface-enhanced Raman scattering (SERS) performance of MWCNTs-NH 2 /dye composite films was investigated. The experimental results showed that MWCNTs-NH 2 /Methylene blue (MB) composite film exhibited good SERS enhancement performance for Rhodamine 6 G (R6G) molecules with an enhanced factor (EF) of 2.16 × 10 5 , and had certain repeatability and uniformity, making it suitable for the detection of trace molecule. The photoelectric conversion efficiency of MWCNTs-NH 2 /dye composite films were also explored. MWCNTs-NH 2 /MB composite film not only exhibited the highest photocurrent value but also had the smallest impedance compared with the other films, indicating that it had lower impedance, better carrier transport rate, and more stable performance. This work provides an effective method for fabricating the composite LB films based on the carbon nanotubes with great SERS and photoelectric conversion efficiency.
研究领域:
材料科学
·
纳米技术
·
光学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Tianyue Zhao,Ran Wang,Shengnan Wei,Lexin Zhang,Zhiwei Liu,Mingli Wang,Tifeng Jiao
In this work, the self-assembled films of sericin protein (SP), silk fibroin (SF), and dye molecules were prepared by the Langmuir-Blodgett (LB) technique. Surface-enhanced Raman scattering (SERS) experiments demonstrated that the SP/saffron T (ST)-80 and SF/ST-60 composite LB films exhibited good Raman enhancement characteristics with enhancement factors (EFs) of 5.74×10 4 and 7.05×10 4 , respectively. The relative standard deviations (RSDs) of Raman intensity were 7.19% and 18.40%, respectively, confirming the uniformity of the composite LB films. Furthermore, photoelectric conversion efficiencies indicate that the electrodes fabricated from SP/ST and SF/ST film electrodes have high carrier rates and good photocurrent generation properties. This study provides novel insights into the fabrication of multifunctional SP/dye and SF/dye composite LB films, demonstrating their potential applications in SERS and photovoltaic conversion.
研究领域:
材料科学
·
生物物理学
✓ 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）