Characterization of Asymmetric Polydiacetylene Ultrathin Films

1995 ◽  
Vol 382 ◽  
Author(s):  
D. W. Cheong ◽  
V. Shivshankar ◽  
H. C. Wang ◽  
C. M. Sung ◽  
J. Kumar ◽  
...  
Keyword(s):  
Ultrathin Films ◽  
Second Harmonic ◽  
Film Deposition ◽  
Asymmetric Structure ◽  
Blodgett Film ◽  
Force Microscopy ◽  
Langmuir Blodgett ◽  
Atomic Force ◽  
Ft Ir

ABSTRACTNonlinear optical (NLO) ultrathin films of a preforrned asymmetric polydiacetylene have been fabricated by Z-type Langmuir-Blodgett film deposition from the air-water interface. Induced in-plane orientation of the polydiacetylene backbone on the substrates has been confirmed by UV/Vis, FT-IR dichroism, and degenerate four wave mixing (DFWM) studies. All the measurements indicate that the backbone is prefe rentially oriented along the dipping direction. Second harmonic generation study suggests that the LB multilayers form an asymmetric structure (Z-type) due to the accumulation of 2-dimensional ordered monolayer and the dominant induced second order polarization is in the plane of the film. The film morphology and molecular orientation have been investigated by atomic force microscopy (AFM).

Structural and Morphological Characterization of Ultrathin Films of an Asymmetric Polydiacetylene

1996 ◽  
Vol 440 ◽  
Author(s):  
H. C. Wang ◽  
D. W. Cheong ◽  
J. Kumar ◽  
C. Sung ◽  
S. K. Tripathy
Keyword(s):  
Second Harmonic ◽  
Morphological Characterization ◽  
Lb Films ◽  
Force Microscopy ◽  
Langmuir Blodgett ◽  
Glass Substrates ◽  
Atomic Force ◽  
Transmission Electron ◽  
Air Water Interface

AbstractA soluble, asymmetrically substituted polydiacetylene, poly(BPOD), has been reported to form stable monolayers at the air-water interface by the Langmuir-Blodgett (LB) technique [2]. Preformed polydiacetylene has been deposited onto hydrophobic substrates as multilayers to form second order nonlinear optical thin films. Second harmonic generation was found to increase with the number of layers. From previous atomic force microscopy (AFM) studies backbone orientation along the dipping direction with an interchain spacing of about 5 A° was indicated [2].The film morphology and preferential molecular orientation of these LB films are further investigated by transmission electron microscopy (TEM). A specifically tailored sample preparation method for the ultrathin LB films was used. Multilayer films were deposited on hydrophobic collodion covered glass substrates for this purpose. Electron diffraction was employed to study the crystalline organization of mono and multilayers of LB films as well as cast films.

Nano scale defects in langmuir-blodgett film observed by atomic force microscopy

1993 ◽  
Vol 57 (1) ◽  
pp. 3795-3800 ◽  
Author(s):  
J. Garnaes ◽  
D.K. Schwartz ◽  
R. Viswanathan ◽  
J.A.N. Zasadzinski
Keyword(s):  
Atomic Force Microscopy ◽  
Blodgett Film ◽  
Force Microscopy ◽  
Langmuir Blodgett ◽  
Nano Scale ◽  
Atomic Force ◽  
Langmuir Blodgett Film

scholarly journals Synthesis and Characterization of PLA-Micro-structured Hydroxyapatite Composite Films

Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 274 ◽  
Author(s):  
Andreea Madalina Pandele ◽  
Andreea Constantinescu ◽  
Ionut Cristian Radu ◽  
Florin Miculescu ◽  
Stefan Ioan Voicu ◽  
...  
Keyword(s):  
Composite Films ◽  
Synthesis Method ◽  
Polymer Chains ◽  
Force Microscopy ◽  
Degradation Temperature ◽  
Atomic Force ◽  
Hydroxyapatite Composite ◽  
Ft Ir ◽  
Ir And Raman

This article presents a facile synthesis method used to obtain new composite films based on polylactic acid and micro-structured hydroxyapatite particles. The composite films were synthesized starting from a polymeric solution in chloroform (12 wt.%) in which various concentrations of hydroxyapatite (1, 2, and 4 wt.% related to polymer) were homogenously dispersed using ultrasonication followed by solvent evaporation. The synthesized composite films were morphologically (through SEM and atomic force microscopy (AFM)) and structurally (through FT-IR and Raman spectroscopy) characterized. The thermal behavior of the composite films was also determined. The SEM and AFM analyses showed the presence of micro-structured hydroxyapatite particles in the film’s structure, as well as changes in the surface morphology. There was a significant decrease in the crystallinity of the composite films compared to the pure polymer, this being explained by a decrease in the arrangement of the polymer chains and a concurrent increase in the degree of their clutter. The presence of hydroxyapatite crystals did not have a significant influence on the degradation temperature of the composite film.

scholarly journals Cellulose-Cyclodextrin Co-Polymer for the Removal of Cyanotoxins on Water Sources

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2075
Author(s):  
Diego Gomez-Maldonado ◽  
Iris Beatriz Vega Erramuspe ◽  
Ilari Filpponen ◽  
Leena-Sisko Johansson ◽  
Salvatore Lombardo ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Cellulose Nanofibrils ◽  
Human Consumption ◽  
Nutrient Runoff ◽  
Force Microscopy ◽  
Atomic Force ◽  
Safe Limits ◽  
Ft Ir ◽  
Recreational Use

With increasing global water temperatures and nutrient runoff in recent decades, the blooming season of algae lasts longer, resulting in toxin concentrations that exceed safe limits for human consumption and for recreational use. From the different toxins, microcystin-LR has been reported as the main cyanotoxin related to liver cancer, and consequently its abundance in water is constantly monitored. In this work, we report a methodology for decorating cellulose nanofibrils with β-cyclodextrin or with poly(β-cyclodextrin) which were tested for the recovery of microcystin from synthetic water. The adsorption was followed by Quartz Crystal Microbalance with Dissipation monitoring (QCM-D), allowing for real-time monitoring of the adsorption behavior. A maximum recovery of 196 mg/g was obtained with the modified by cyclodextrin. Characterization of the modified substrate was confirmed with Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Photoelectron Spectroscopy (XPS), Thermogravimetric Analysis (TGA), and Atomic Force Microscopy (AFM).

scholarly journals Characterization of the Spindle Morphology Nanomicelles Assembled from Sericin and Gelatin

2017 ◽  
Vol 2017 ◽  
pp. 1-9
Author(s):  
Xiaozhou Su ◽  
Lei Li ◽  
Weihan Huang
Keyword(s):  
Electron Microscopy ◽  
Protein Concentration ◽  
Scanning Calorimetry ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Ft Ir ◽  
And Storage ◽  
Ft Ir Spectroscopy

Complex nanomicelles were prepared by sericin and type A gelatin with molecular weight of 5789 Da and 128664 Da separately. The assembling conditions were as follows: mass ratio (sericin/gelatin) was 1 : 1, protein concentration was 0.5%, temperature was 35°C, and assembling time was 18 hours. Scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), and dynamic light scattering (DLS) were conducted to observe and characterize the complex nanomicelles. Results showed that the complex sericin/gelatin micelles was a kind of nanospindle micelles. The micelles had high electrochemical stability, thermal stability, antidilution stability, and storage stability.

Efficient approach for optical and morphologic characterization of hybrid perovskite films based on reflectance and transmittance measurements

2021 ◽  
Author(s):  
Jorge Caram ◽  
Maximiliano Senno ◽  
Luisa Cencha ◽  
Silvia Tinte ◽  
Raul Urteaga ◽  
...  
Keyword(s):  
Low Cost ◽  
Normal Incidence ◽  
Film Deposition ◽  
Morphological Properties ◽  
Efficient Procedure ◽  
Force Microscopy ◽  
Atomic Force ◽  
Hybrid Perovskite

Abstract Organo-inorganic perovskites have been intensively studied due to its potential application in low cost and great efficient energy conversion in solar cells. Despite the great improvement in the quality of organo-inorganic perovskite films, a wide dispersion into the same batch of perovskite-based devices keep being an obstacle to obtaining highly reproducible results. For that reason new and efficient strategies for testing deposition results is imperative for the next step. Here we present a simple and efficient procedure for characterizing the optical and morphological properties based on the simultaneous reflectance and transmittance measurements under normal incidence over a MAPbI3 film. The proposed method provides qualitative and quantitative morphological information associated with the film roughness as well as information about the position of the optical gap and possible contributions to the optical dispersion in the structure that can be used as a simple diagnostic tool to optimize the film deposition. Results are contrasted and validated with electronic and atomic force microscopy, as well as first-principles calculations.

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