ESCA as a Tool for Exploration of Metals’ Surface

Abstract

The main principles and development of electron spectroscopy for chemical analysis (ESCA) are briefly reviewed. The role of ESCA techniques (X-ray photoelectron spectroscopy and Auger electron spectroscopy) in the investigation of metallic surfaces is discussed, evidencing their importance and analytical potentiality. An overview is given of a series of recent experimental cases of ESCA application for the characterization of different metals and metallic alloys, illustrating the main results and various phenomena, such as the formation of impurity defects, corrosion, migration of constituent elements in various alloys, clustering in liquid alloy, etc., that can occur on the surface and the interface of investigated materials. These materials comprise the collection coins of noble metals, some metal alloys and Ni-based superalloys, nitride coatings on stainless steel, composite material with TiAlV alloy, treated austenitic steels, and graphene interface with polycrystalline metal foils. The present review could be particularly recommended for the newcomers to the research field of surface analysis and its application for various metals, their treatments, and possible modifications in operating conditions.

Charge Transport Mechanisms of Black Diamond at Cryogenic Temperatures

“…All XPS data were collected and processed by the Avantage v.5 software (Thermo Fisher Scientific, Altrincham, UK). More details are reported elsewhere [24].…”

First-Principles Estimation of Core Level Shifts for Hf, Ta, W, and Re

“…X-ray photoelectron spectroscopy (XPS) is a powerful tool for the chemical analysis of near-surface atoms in the solid state and uses the fact that the binding energies of the core electron states are only weakly affected by the environment of a given atom (many textbooks discuss the definition of binding energy; for example, see Huefner), leading to the ability to identify the presence of a chemical element by its XPS spectrum. However, the small shifts in the energy of a given core level are frequently measurable and can be diagnostic of the chemical environment of the atom. , Nowadays, XPS is considered a mature characterization technique: this is due to (i) the availability of a huge database of XPS spectra in the literature for all of the elements in the periodic table in different environments and compounds, (ii) the availability of lab equipment with bright and focused photon sources and advanced electron analyzers, allowing for bidimensional real-space or k -space mapping with submicrometer lateral resolution, , (iii) the exploitation of the photon tunability and high-energy resolution achievable at synchrotron light sources which couple a high brightness with a continuous range of excitation energies. A free choice of excitation energy also means that the investigator has some control over the core level photoabsorption cross section and over the depth below the surface over which the photoemitted electrons escape and can be detected…”

Surface NMR using quantum sensors in diamond

“…Therefore, it remains challenging to perform chemical analysis under the conditions in which these processes occur [2,3]. Typical surfacesensitive methods, such as X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy and secondary ion mass spectroscopy (SIMS) can perform chemical analysis but require ultra-high vacuum conditions and expensive equipment [4]. To address this gap, great efforts have been devoted to extending XPS analysis to near ambient conditions [2].…”