Search Results for surface enhanced Raman spectroscopy

This article describes the analytical methods for analyzing surfaces for corrosion and corrosion inhibition processes as well as failure analysis based on surface structure and chemical identity and composition. The principles and applications of the surface-structure analysis techniques, namely, optical microscopy, scanning electron microscopy, scanning tunneling microscopy, and atomic force microscopy, are reviewed. The article discusses the principles and applications of chemical identity and composition analysis techniques. These techniques include the energy dispersive X-ray spectroscopy, Auger electron spectroscopy, X-ray photoelectron spectroscopy, ion scattering spectroscopy, reflectance Fourier transform infrared absorption spectroscopy, Raman and surface enhanced Raman spectroscopy, and extended X-ray absorption fine structure analysis.

This article introduces the principles of Raman spectroscopy and the representative materials characterization applications to which Raman spectroscopy has been applied. A discussion on light-scattering fundamentals and a description of the experimental aspects of the technique are included. Emphasis is placed on the different instrument approaches that have been developed for performing Raman analyses on various materials. The applications presented reflect the breadth of materials characterization uses for Raman spectroscopy and highlight the analysis of bulk material and of surface and near-surface species.

This article introduces the principles of Raman spectroscopy and the representative materials characterization applications to which Raman spectroscopy has been applied. It includes a discussion of light-scattering fundamentals and a description of the experimental aspects of the technique. Emphasis has been placed on the different instrument approaches that have been developed for performing Raman analyses on various materials. The applications presented in the article reflect the breadth of materials characterization uses for Raman spectroscopy and highlight the analysis of bulk material and of surface and near-surface species.

This article focuses on the modes of operation, physical basis, sample requirements, properties characterized, advantages, and limitations of the characterization methods used to evaluate the physical morphology and chemical properties of component surfaces for medical devices. These methods include light microscopy, scanning electron microscopy, atomic force microscopy, energy-dispersive X-ray spectroscopy, Auger electron spectroscopy, secondary ion mass spectrometry, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy.

This article provides an introduction to the molecular fluorescence spectroscopy, and discusses the theory of fluorescence and its application to chemical analysis. It provides information on fluorescence that occurs in organic compounds and inorganic atoms and molecules. The article describes the instruments used in the spectroscopy, namely, radiation sources, sample holders, wavelength selectors, detectors, computers, and ratiometric instruments. The practical considerations include solvent effects, corrected spectra, wavelength calibration, temperature, and scattered light. The article also discusses the uses of some special techniques used in molecular fluorescence spectroscopy.

Infrared (IR) spectra have been produced by transmission, that is, transmitting light through the sample, measuring the light intensity at the detector, and comparing it to the intensity obtained with no sample in the beam, all as a function of the infrared wavelength. This article discusses the sampling techniques and applications of IR spectra as well as the molecular structure information it can provide. The discussion begins with a description of the general principle of IR spectroscopy. This is followed by a section on commercial IR instruments. Sampling techniques and accessories necessary in obtaining the infrared spectrum of a material are then discussed. The article presents various techniques and methods involved in IR qualitative analysis and quantitative analysis. It ends with a few examples of the applications of IR spectroscopy.

The characterization, testing, and nondestructive evaluation of ceramics and glasses are vital to manufacturing control, property improvement, failure prevention, and quality assurance. This article provides a broad overview of characterization methods and their relationship to property control, both in the production and use of ceramics and glasses. Important aspects covered include the means for characterizing ceramics and glasses, the corresponding rationale behind them, and relationship of chemistry, phases, and microconstituents to engineering properties. The article also describes the effects that the structure of raw ceramic materials and green products and processing parameters have on the ultimate structure and properties of the processed piece. The effects that trace chemistry and processing parameters have on glass properties are discussed. The article describes mechanical tests and failure analysis techniques used for ceramics.

This article is a compilation of terms and definitions related to materials characterization.

This article introduces various techniques commonly used in the characterization of semiconductors, namely single-crystal, polycrystalline, amorphous, oxide, organic, and low-dimensional semiconductors and semiconductor devices. The discussion covers material classification, fabrication methods, sample preparation, bulk/elemental characterization methods, microstructural characterization methods, surface characterization methods, and electronic characterization methods.

This article describes two variations of carbon-base coatings: diamondlike carbon (DLC) coatings and polycrystalline diamond (PCD) coatings. It discusses the basics of a few deposition methods as they apply to industrially relevant coatings. The methods include deposition of tungsten-containing hydrogenated amorphous carbon films, deposition of tetrahedral amorphous carbon films, and deposition of silicon-incorporated hydrogenated amorphous carbon films. The most common deposition technologies for diamond films are also discussed. The article provides information on surface preparation for DLC and diamond deposition. It also provides a discussion on the coating composition and structure, mechanical and tribological properties, and applications of DLC and diamond coatings. The quality control techniques for DLC and diamond coatings are specified to meet customer requirements and ensure repeatable quality.

Infrared (IR) spectroscopy is a useful technique for characterizing materials and providing information on the molecular structure, dynamics, and environment of a compound. This article provides the basic principles and instrumentation of IR spectroscopy. It discusses the sampling techniques of IR spectroscopy, namely, attenuated total reflectance spectroscopy, diffuse reflectance spectroscopy, infrared reflection-absorption spectroscopy, emission spectroscopy, and photoacoustic spectroscopy, and chromatographic techniques. Explaining the qualitative analysis of IR spectroscopy, the article provides information on spectral absorbance-subtraction, analysis of components in spectral matrix mixture, and determination of exact peak location of broad profiles. It discusses the quantitative analysis that mainly includes Beer's law for single compound in single wave number. The article also exemplifies the applications of IR spectroscopy.

Coatings and thin films can be studied with surface analysis methods because their inherently small depth allows characterization of the surface composition, interface composition, and in-depth distribution of composition. This article describes principles and examples of common surface analysis methods, namely, Auger electron spectroscopy, X-ray photoelectron spectroscopy, ion scattering spectroscopy, secondary ion mass spectroscopy, and Rutherford backscattering spectroscopy. It also provides useful information on the applications of surface analysis.

Fiber-matrix adhesion is a variable to be optimized in order to get the best properties and performance in composite materials. This article schematically illustrates fiber matrix interphase for composite materials. It discusses thermodynamics of interphase in terms of surface energy, contact angle, work of adhesion, solid surface energy, and wetting and wicking. The article describes the change in interphase depending on the reinforcing fiber such as glass fiber, polymeric fiber, and carbon fiber. It emphasizes fiber-matrix adhesion measurements by direct methods, indirect methods, and composite laminate tests. The effects of interphase and fiber-matrix adhesion on composite mechanical properties, such as composite on-axis properties, composite off-axis properties, and composite fracture properties, are also discussed.

This article is a compilation of abbreviations, symbols, and tradenames for terms related to the properties, selection, processing, and applications of the most widely used nonmetallic engineering materials.