PDF Publication Title:
Text from PDF Page: 072
2.4 X-ray Photoelectron Spectroscopy Figure 2.9: Exemplary XPS spectra of Ni2p3/2 that show a complicated composition of the nickel envelope - The presented envelopes come from a. clean nickel metal, b. NiO fitted with Ni(II) multiplet structure, c. Ni(OH)2 fitted with Ni(II) multiplet envelope. As presented in (43) From these spectra one can conclude that it is almost impossible to ascribe a single peak to one particular ionic state. In order to resolve the spectra, a whole envelope of peaks corresponding to a particular ionic state should be taken into account. Only such envelopes in total should contribute to quantitative investi- gation of chemical state of a transition metal ion (11). The measurements described in this work were taken with multi-technique electron spectrometer, model PHI 5700/660 from Physical Electronics. The monochro- matized Al Kα radiation was used. It enables probing the core electron states down to 1486.6 eV reduced by the work function of the spectrometer. The energy resolution depended on chosen parameters of the spectrometer, the measurement range and specific spectral lines. In order to investigate the transition, spectra were recorded at various temperatures starting as low as about the liquid ni- trogen temperature up to over 400 K, that is below and over metal-insulator transition for SmNiO3. All experiments were conducted in ultra-high vacuum. The electrons that left the surface at a take-off angle of 45◦ were detected. In XPS, the weakly or non-conducting materials are more difficult to study as there is a common risk of charge build-up which can mask the true electronic structure. If there is not enough of delocalized, conduction electrons to fill the photoelectron holes, the near-surface positive potential arises. This potential acts on the escaping electrons and modifies their kinetic energy. Such are the SmNiO3 films and most of RNiO3 compounds in a wide temperature range, below MIT. The effect may be overcome by supplying slow electrons just above a sample surface to neutralize the artificial positive potential. However this raises questions on a proper neutralization of the artificial positive potential. The charging effect depends also on the sampling depth. It is important to provide a good electrical 51PDF Image | Investigation of metal-insulator transition in magnetron sputtered samarium nickelate thin films
PDF Search Title:
Investigation of metal-insulator transition in magnetron sputtered samarium nickelate thin filmsOriginal File Name Searched:
Bilewska_Investigation_of_metal_insulator_transition_in_magnetron_sputtered_samarium.pdfDIY PDF Search: Google It | Yahoo | Bing
Sulfur Deposition on Carbon Nanofibers using Supercritical CO2 Sulfur Deposition on Carbon Nanofibers using Supercritical CO2. Gamma sulfur also known as mother of pearl sulfur and nacreous sulfur... More Info
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)