Emerging Microscopy Techniques

Cathodoluminescence (CL), i.e., the emission of light as the result of electron-beam bombardment, was first reported in the middle of the nineteenth century in experiments in evacuated glass tubes. The tubes were found to emit light when an electron beam (cathode ray) struck the glass, and subsequendy this phenomenon led to the discovery of the electron. Currendy, cathodoluminescence is widely used in cathode-ray tube-based (CRT) instruments (e.g., oscilloscopes, television and computer terminals) and in electron microscope fluorescent screens. With the developments of electron microscopy techniques (see the articles on SEM, STEM and TEM) in the last several decades, CL microscopy and spectroscopy have emerged as powerfirl tools for the microcharacterization of the electronic propenies of luminescent materials, attaining spatial resolutions on the order of 1 pm and less. Major applications of CL analysis techniques include ... 

The direct visnalization of microstructure may be accomplished by various forms of microscopy. Recent refinements in microscopy techniques are epitomized by video-enhanced interference phase-contrast microscopy, which is emerging as a workhorse probe for colloidal suspensions and other microstructnred liqnids. 

All emerging scanning probe techniques, which appear superior to previous electron microscopy techniques in many respects, have been collected, insofar as they are related to photochemistry and spectroscopy. All of these recent techniques will certainly find application. 

The aim of this edition is to provide an up-to-date account of these recent advances. The first chapter describes a fascinating application of the X-ray diffraction technique to the study of the structure-reactivity relationship in electrocatalysis. The next two chapters illustrate the power of UV-visible spectroscopy and epifluorescence microscopy to explore electric field-driven transformations of thin organic films. Two chapters are devoted to non-linear spectroscopies at the liquid-liquid and liquid-solid interfaces, demonstrating the uniqueness of these techniques for revealing the structural details of these buried interfaces. Four chapters give a comprehensive description of applications of infrared spectroscopy to in-situ studies of electrified semiconductor-solution and metal-solution interfaces. The volume is concluded by a chapter that describes the emerging new technique of STM tip-induced surface-enhanced Raman spectroscopy. 

Finally, application of other methods of analysis can be recommended. Many of the previous electrochemical studies devoted to conducting polymers were carried out in combination with radiotracer technique, AC electrogravimetry, quartz-crystal microbalance, surface plasmon resonance, and even ellipsometry, and atomic-force microscopy. In this context application of emerging experimental techniques such as local EIS and nonlinear impedance analysis may also be recommended. 

Certain chromophore systems are intrinsically predisposed for ultrafast single molecule microscopy. Among these, emitters coupled to metal surfaces stand out as exceptionally well-suited subjects. Numerous observations of substantial radiative rate enhancement at the surface or in the vicinity of the surface of a metal were reported. Radiative rate enhancements as large as 10 have been predicted for molecular fluorophores and for semiconductor quantum dots coupled to optimized nanoantennae.Such accelerated emission rates put these systems well within the reach of the emerging femtosecond microscopy techniques. As a result, we decided to apply the Kerr-gated microscope to study of fluorescence dynamics of individual core-shell quantum dots in contact with smooth and nanostructured metal surfaces. 

Until quite recently the very initial stages of metal deposition were difficult to characterize in detail by structure- and morphology-sensitive techniques. As a consequence and for practical purposes - multilayers were more useful for applications than monolayers - the main interest was focussed onto thick deposits. Optical and electron microscopy, ellipsometry and specular or diffuse reflectance spectroscopy were the classic tools, by which the emerging shape of the deposit was monitored [4-7],... 

With these emerging applications, there is a critical need for analytical techniques that will provide insights to fundamental questions concerning dendrimer characteristics and properties (e.g. their dimensions, uniformity of size, shape and degree of rigidity, etc.) [8-10], atomic force microscopy (AFM) offers this... 

Around 1980 a new method of microscopy known as scanning probe microscopy (SPM) was invented. Within the past ten years, applications have been increasing exponentially in fields like surface physics and chemistry, biology and optics. SPM is also beginning to emerge as a usefvil and popular technique for R D and quality control in several industries. 

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