Theoretical Investigation of Tip-Based Nanoscale Infrared Spectroscopy

2009 ◽  
Author(s):  
William Dipippo ◽  
Bong Jae Lee ◽  
Keunhan Park
Keyword(s):  
Ir Spectroscopy ◽  
Chemical Analysis ◽  
Chemical Information ◽  
Full Spectrum ◽  
Force Microscopy ◽  
Chemical Force Microscopy ◽  
Atomic Force ◽  
Ft Ir ◽  
Tip Enhanced Raman Spectroscopy

The ability to conduct the chemical analysis of materials with the nanoscale spatial resolution has been a long term thrust in many science and engineering communities. Although several techniques such as chemical force microscopy [1] and tip-enhanced Raman spectroscopy [2] have been developed for the nanoscale chemical analysis, there still exist technical challenges in routinely achieving a full spectrum of chemical information at the nanoscale. The main objective of this study is to propose a novel tip-based nanoscale infrared (IR) spectroscopy by combining the atomic force microscopy (AFM) and the Fourier-transformed infrared (FT-IR) spectroscopy.

scholarly journals Tip Recycling for Atomic Force Microscopy-Based Tip-Enhanced Raman Spectroscopy

2020 ◽  
Vol 74 (11) ◽  
pp. 1358-1364
Author(s):  
Giovanni Luca Bartolomeo ◽  
Guillaume Goubert ◽  
Renato Zenobi
Keyword(s):  
Raman Spectroscopy ◽  
Atomic Force Microscopy ◽  
Visible Range ◽  
Chemical Information ◽  
Plasmonic Enhancement ◽  
Single Experiment ◽  
Force Microscopy ◽  
Atomic Force ◽  
Tip Enhanced Raman Spectroscopy ◽  
Reducing Costs

Tip-enhanced Raman spectroscopy (TERS) is a powerful tool for the characterization of surfaces and two-dimensional materials, delivering both topographical and chemical information with nanometer-scale spatial resolution. Atomic force microscopy (AFM)–TERS combines AFM with a Raman spectrometer and is a very versatile technique, capable of working in vacuum, air, and liquid, and on a variety of different samples. A metalized AFM tip is necessary in order to take advantage of the plasmonic enhancement. The most commonly used metal is Ag, thanks to its high plasmonic activity in the visible range. Unfortunately, though, the tip metallization process is still challenging and not fully reliable, yielding inconsistent enhancement factors even within the same batch of tips; as a consequence, many tips are usually prepared at once (for a single experiment), to ensure that at least one of them is sufficiently active. As the lifetime of an unprotected, Ag-coated plasmonic probe is only a few hours, the procedure is inefficient and results in a substantial waste of materials and money. In this work, we establish a cleaning routine to effectively re-use Ag-coated AFM–TERS probes, drastically reducing costs without compromising the quality of the experimental results.

scholarly journals Modification in surface properties of poly-allyl-diglycol-carbonate (CR-39) implanted by Au+ ions at different fluences

2016 ◽  
Vol 34 (2) ◽  
pp. 468-478 ◽  
Author(s):  
Riffat Sagheer ◽  
M. Shahid Rafique ◽  
Farhat Saleemi ◽  
Shafaq Arif ◽  
Fabian Naab ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Ir Spectroscopy ◽  
Ion Implantation ◽  
Surface Properties ◽  
Force Microscopy ◽  
Atomic Force ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Insulating Polymers ◽  
Ft Ir Spectroscopy

AbstractIon implantation has a potential to modify the surface properties and to produce thin conductive layers in insulating polymers. For this purpose, poly-allyl-diglycol-carbonate (CR-39) was implanted by 400 keV Au+ ions with ion fluences ranging from 5 × 1013 ions/cm2 to 5 × 1015 ions/cm2. The chemical, morphological and optical properties of implanted CR-39 were analyzed using Raman, Fourier transform infrared (FT-IR) spectroscopy, atomic force microscopy (AFM) and UV-Vis spectroscopy. The electrical conductivity of implanted samples was determined through four-point probe technique. Raman spectroscopy revealed the formation of carbonaceous structures in the implanted layer of CR-39. From FT-IR spectroscopy analysis, changes in functional groups of CR-39 after ion implantation were observed. AFM studies revealed that morphology and surface roughness of implanted samples depend on the fluence of Au ions. The optical band gap of implanted samples decreased from 3.15 eV (for pristine) to 1.05 eV (for sample implanted at 5 × 1015 ions/cm2). The electrical conductivity was observed to increase with the ion fluence. It is suggested that due to an increase in ion fluence, the carbonaceous structures formed in the implanted region are responsible for the increase in electrical conductivity.

Novel Method for High-Spatial-Resolution Chemical Analysis of Buried Polymer-Metal Interface: Atomic Force Microscopy-Infrared (AFM-IR) Spectroscopy with Low-Angle Microtomy

2021 ◽  
pp. 000370282110071
Author(s):  
Naoki Baden
Keyword(s):  
Atomic Force Microscopy ◽  
Ir Spectroscopy ◽  
Chemical Analysis ◽  
Cross Section ◽  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Force Microscopy ◽  
Atomic Force ◽  
Polymer Metal ◽  
Metal Interfaces

There is a great need for the analysis of the chemical composition, structure, functional groups, and interactions at polymer-metal interfaces in terms of adhesion, corrosion, and insulation. Although atomic force microscopy-based infrared (AFM-IR) spectroscopy can provide chemical analysis with nanoscale spatial resolution, it generally requires to thin a sample to be placed on a substrate that has low absorption of infrared light and high thermal conductivity, which is often difficult for samples that contain hard materials such as metals. This study demonstrates that the combination of AFM-IR with low-angle microtomy (LAM) sample preparation can analyze buried polymer-metal interfaces with higher spatial resolution than that with the conventional sample preparation of a thick vertical cross-section. In the LAM of a polymer layer on a metal substrate, the polymer layer is tapered to be thin in the vicinity of the interface, and thus, sample thinning is not required. An interface between an epoxyacrylate layer and copper wire in a flexible printed circuit cable was measured using this method. A carboxylate interphase layer with a thickness of ∼130 nm was clearly visualized at the interface, and its spectrum was obtained without any signal contamination from the neighboring epoxyacrylate, which was difficult to achieve on a thick vertical cross-section. The combination of AFM-IR with LAM is a simple and useful method for high-spatial-resolution chemical analysis of buried polymer-metal interfaces.

scholarly journals Preparation, Thermal, and Thermo-Mechanical Characterization of Polymeric Blends Based on Di(meth)acrylate Monomers

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 878
Author(s):  
Krystyna Wnuczek ◽  
Andrzej Puszka ◽  
Łukasz Klapiszewski ◽  
Beata Podkościelna
Keyword(s):  
Mechanical Analysis ◽  
Attenuated Total Reflection ◽  
Scanning Calorimetry ◽  
Force Microscopy ◽  
Chemical Structures ◽  
Atomic Force ◽  
Polymeric Blends ◽  
Ft Ir ◽  
Acrylate Monomers ◽  
Synthesized Materials

This study presents the preparation and the thermo-mechanical characteristics of polymeric blends based on di(meth)acrylates monomers. Bisphenol A glycerolate diacrylate (BPA.GDA) or ethylene glycol dimethacrylate (EGDMA) were used as crosslinking monomers. Methyl methacrylate (MMA) was used as an active solvent in both copolymerization approaches. Commercial polycarbonate (PC) was used as a modifying soluble additive. The preparation of blends and method of polymerization by using UV initiator (Irqacure® 651) was proposed. Two parallel sets of MMA-based materials were obtained. The first included more harmless linear hydrocarbons (EGDMA + MMA), whereas the second included the usually used aromatic copolymers (BPA.GDA + MMA). The influence of different amounts of PC on the physicochemical properties was discussed in detail. Chemical structures of the copolymers were confirmed by attenuated total reflection–Fourier transform infrared (ATR/FT-IR) spectroscopy. Thermo-mechanical properties of the synthesized materials were investigated by means of differential scanning calorimetry (DSC), thermogravimetric (TG/DTG) analyses, and dynamic mechanical analysis (DMA). The hardness of the obtained materials was also tested. In order to evaluate the surface of the materials, their images were obtained with the use of atomic force microscopy (AFM).

Effect of Catalysts on the Properties of Fluorinated Polyurethanes

2013 ◽  
Vol 464 ◽  
pp. 9-13 ◽  
Author(s):  
Zan Li ◽  
Xia Wang ◽  
Ying Li ◽  
Wei Chain ◽  
Jiao Jiao Hu
Keyword(s):  
Hard Segment ◽  
Soft Segment ◽  
Force Microscopy ◽  
Atomic Force ◽  
Structure Surface ◽  
Improved Stability ◽  
Ft Ir ◽  
Tin Metal ◽  
Polyether Polyol ◽  
Catalyst Efficiency

Fluorinated polyurethanes (FPU) was prepared using fluorinated polyether polyol (FPO) as the soft segment, 4,4`-diphenylmethane diisocyanate (MDI) as the hard segment, 1,4-butanodiol (BDO) as the chain extender and catalysts. Tin metal catalysts were used to catalyze the polyurethane reaction of polyether polyols and isocyanate. The effect of different catalysts including stannous octoate (T-9) and dibutyltindalautrate (DBTDL) on the structure, surface properties and thermal properties of FPU was studied. The structural elucidation of the synthesized FPU was performed by Fourier transform infrared (FT-IR) and discovered that with decreasing catalyst efficiency or without catalyst, the strength of hydrogen bounds were enhanced. The FPU films surface was characterized by contact angle (CA) and atomic force microscopy (AFM) and it was found that the phase separation was increasing with increasing catalyst efficiency. The thermal property was exhibited by Thermo gravimetric (TG) and showed that joining catalyst improved stability significantly.

scholarly journals Strategy For Cellulase Immobilization And Its Partial Purification And Characterization

2021 ◽  
Author(s):  
Karina Komarova
Keyword(s):  
Active Site ◽  
Partial Purification ◽  
Purification Step ◽  
Purification And Characterization ◽  
Force Microscopy ◽  
Glycosidic Bonds ◽  
Atomic Force ◽  
Lower Glucose ◽  
Force Profile

Conversion of cellulose to glucose units by cellulases, called hydrolysis, is a very complex step in ethanol production. It requires the mixing of aqueous suspensions of cellulose/cellulases so that cellulases (majority composed of the active site domain and the binding site domain) can attach to cellulose chains, cut or hydrolyze ß(1-4) glycosidic bonds between glucose units, de-attach and move to another location. Mixing extent (insufficient or excessive agitation) might influence the attachment of cellulases and possibly lead to lower glucose yields. A long-term goal of this research is to determine the strength of mixing required to be applied during the cellulose-cellulase mixing cycle. For that purpose, one of the objectives was to purify CBH I exocellulase from the commercial cellulase mixture. A partial purification of the CBH I that was performed on a much smaller scale with uncontrolled flow rate was successful. Another objective was to propose a scheme that would covalently immobilize CBH I exoceullase via its active site domain (ASD) on an atomic force microscopy-compatible support, a silicon support. A theoretically-developed hypothetical scheme was constructed (with the provided detailed procedure). The approach of immobilizing the inhibitor specific to the ASD of CBH I enzyme led to the possibility that no purification of CBH I could be required. Skipping CBH I purification step would save time and hassle associated with purification step. Once the ASD of CBH I is immobilized on a silicon support, the AFM force profile between the free-floating CDB and substrate cellulose could be established.

scholarly journals Optical, Structural and Electrical Properties of Electrochemical Synthesis of Thin Film of Polyaniline

2018 ◽  
Vol 15 (1) ◽  
pp. 73-80 ◽  
Author(s):  
Baghdad Science Journal
Keyword(s):  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Morphological Studies ◽  
Atomic Force ◽  
Vis Spectroscopy ◽  
Structural And Electrical Properties ◽  
A Cell ◽  
Ft Ir ◽  
Ir And Raman

Polyaniline membranes of aniline were produced using an electrochemical method in a cell consisting of two poles. The effect of the vaccination was observed on the color of membranes of polyaniline, where analysis as of blue to olive green paints. The sanction of PANI was done by FT-IR and Raman techniques. The crystallinity of the models was studied by X-ray diffraction technique. The different electronic transitions of the PANI were determined by UV-VIS spectroscopy. The electrical conductivity of the manufactured samples was measured by using the four-probe technique at room temperature. Morphological studies have been determined by Atomic force microscopy (AFM). The structural studies have been measured by (SEM).

GROWTH AND STUDIES OF PROPERTIES OF COPPER SUCCINATE DIHYDRATE SINGLE CRYSTALS

2013 ◽  
Vol 27 (11) ◽  
pp. 1350073
Author(s):  
M. P. BINITHA ◽  
P. P. PRADYUMNAN
Keyword(s):  
Differential Scanning Calorimetry ◽  
Dielectric Constant ◽  
Single Crystals ◽  
Scanning Calorimetry ◽  
Force Microscopy ◽  
Atomic Force ◽  
Different Temperatures ◽  
Triclinic Structure ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

Single crystals of copper succinate dihydrate (CSD) with triclinic structure were grown in silica gel medium. The functional groups in the crystal were analyzed by FT-IR Spectroscopy. Atomic Force Microscopy (AFM) revealed the striations on the surface of grown crystals, which were incorporated during its time of growth. Thermal degradation studies have been carried out by Differential Scanning Calorimetry (DSC). Dielectric constant and AC conductivity have been estimated as a function of frequency at different temperatures.

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