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2 Nanofibers
Published in It-Meng Low, Hani Manssor Albetran, Victor Manuel de la Prida Pidal, Fong Kwong Yam, Nanostructured Titanium Dioxide in Photocatalysis, 2021
It-Meng Low, Hani Manssor Albetran, Victor Manuel de la Prida Pidal, Fong Kwong Yam
XPS quantitative analysis, which is usually performed in the low-resolution mode, cannot provide evidence of the presence of V in the ion-implanted sample because XPS peaks that originate from elements with low concentration are not clearly visible. V was detected using high-resolution XPS, but this technique is applied mainly for qualitative analysis rather than quantitative analysis. The V2p line spectrum of V appears at ~513 eV. If we assume that the inelastic mean free path (IMFP) of scattered electrons for V is ~1.25 nm, then a mean depth of analysis of approximately 3.75 nm is obtained.
Nanoscale Characterization
Published in Ram K. Gupta, Sanjay R. Mishra, Tuan Anh Nguyen, Fundamentals of Low Dimensional Magnets, 2023
Arvind Kumar, Swati, Manish Kumar, Neelabh Srivastava, Anadi Krishna Atul
The electrons with higher energy than the prior expression will follow the path of a larger radius than its mean value; similarly, lower energy electrons follow a smaller radius. The distance traveled by an electron inside the material between successive inelastic collisions is introduced as inelastic mean free path (IMFP). The values of IMFP are unique for each element and substrate or solid material matrix of which the element is a part [35–36].
Characterization of physical and mineralogical properties of anthracite and bituminous coal tailings
Published in International Journal of Coal Preparation and Utilization, 2021
Min Liew, Ming Xiao, Shimin Liu
The percentages of the species found on each coal tailings sample were summarized in Tables 2, 3, and 4. The atom percentage or concentration of each element in a sample was calculated by its corresponding intensity peak divided by the total peak areas of all elements detected, scaled with the relative sensitivity factors (RSFs). The RSFs account for the X-ray cross section and inelastic mean free path of the electrons. The summation of the minerals, fixed carbons, and functionalized carbons in Table 4 do not add to 100% possibly because of some incorrect assumptions on the mineral stoichiometry such as the presence of hydroxide species (OH).
A comprehensive study of the structural, elastic, electronic, and optical properties of the tetragonal sodium chalcogenides NaAlX 2 (X = O, S, Se, Te)
Published in Philosophical Magazine, 2022
T. Helaimia, A. Benmakhlouf, M. Bouchenafa, I. Messahli, S. Maabed, F. Khamloul, M. Sidoumou, A. Bouhemadou
Electronic energy loss function (ELF) is the first quantifier of the interaction between a material and rapidly moving electrons through it. The ELF characterises the probability of a scattering event in which the moving electron transfers an energy and a momentum to the medium. The transferred energy takes two forms: plasmons or single-electron excitations. Plasmons are a collective oscillation of the valence electrons and their energy is associated with the density of valence electrons [60]. Determination of the energy loss function allows understanding elementary solid-state interactions and, in particular, the determination of the inelastic mean free path [61]. The energy loss function is expressed as the imaginary part of the negative inverse dielectric function: The real and imaginary parts of the dielectric function; and, respectively, can be used to characterise topographies in the energy-loss spectra. Features located at energies where the curve crosses zero (passes from negative value to positive value) indicate collective excitations known as plasmons. On the other hand, features occurring at energies where is small but nonzero correspond to collective excitations (non-plasmon). Finally, features of the EPF spectra where the imaginary part is large are attributed to single-particle interband excitations [62]. The energy-loss spectra of the studied compounds are illustrated in Figure 6. The ELF spectrum of the NaAlO2 compound is distinguished from those of the other compounds by having initial slop between 10 and 20 eV. The corresponding transitions have single-particle interband character as evidence by the peak in the imaginary part. In the energy range from 18 to 20 eV in NaALO2; from17 to 19 eV in NaAlS2; from 15.5 to 18 eV in NaAlSe2; from 14 to 16 eV in NaAlTe2, the ELF feature has been characterised as a bulk plasmon. In all cases, the real part passes through zero (going from negative value to positive value) at ∼18.81 eV in NaALO2; ∼17.75 eV in NaAlS2; ∼16.26 eV in NaAlSe2; ∼15.17 eV in NaAlTe2. The peaks in the ELF function are associated with the plasma resonance and the corresponding energy is called plasmon energy. The obtained plasmon energy for the [100] ([001]) polarisation is 22.50 eV (22.17 eV) in NaALO2; 17.92 eV (17.88 eV) in NaAlS2, 17.34 eV (17.27 eV) in NaAlSe2; 15.73 eV (15.69 eV) in NaAlTe2.