X‐ray photoelectron imaging of germanosilicate optical fibre preforms

Abstract

The germanosilicate glass core (GeO,SiO,) of an optical fibre preform has been analysed and imaged using small-spot (-450 pm) x-ray photoelectron spectroscopy (XPS). The germanium oxide was most readily detected in the glass preform sample using the AI K, x-ray-induced Ge L,MM Auger feature. The observed Ge L,MM lineshape and estimated oxidation state shift of 8.8 eV with respect to pure germanium indicate that the germanium is predominantly in the form of GeO, (+ 4 oxidation state) within the germanosilicate core. Argon ion etching was found to sputter preferentially the oxygen from the glass, and the observed changes in Ge L,MM Auger lineshapes suggest that suboxide defects (GeO) are produced. Quantitative XPS images and linescans were used to map the spatial distribution of germanium within the preform and were in good agreement with measured refractive index profiles.

A Battery Made from a Single Material

“…Figure b demonstrates the high resolution Ge 3d spectra of the LGPS anodes at the fresh, fully discharged (to 0.0 V) and fully charged (to 2.0 V) states. For the fresh LGPS anode, the main peak positioned at 30.3 eV could be attributed to the GeS 4 tetrahedra in the LGPS, while the other two small peaks at 31.3 and 33.3 eV stand for the Ge–S and Ge–O from the impurities or contaminants on the surface, respectively. However, for the fully discharged and fully charged LGPS anodes, the main Ge 3d peak at 30.3 eV shifted to a high binding energy at 31.3 eV, while a new peak at 29.7 eV appeared.…”

Application of quantitative X‐ray photoelectron spectroscopy (XPS) imaging: investigation of Ni‐Cr‐Mo alloys exposed to crevice corrosion solution

“…Routine XPS imaging has been around for approximately two decades . The initial approach involved collecting XPS images at a specific energy and then subtracting and dividing by the background.…”

Porous Ge@C materials via twin polymerization of germanium(ii) salicyl alcoholates for Li-ion batteries

“…However, the XPS data are also consistent with data reported for germanium oxides. [75][76][77][78][79][80][81][82][83][84][85] Thus the XPS data do not allow to differentiate between the presence of Ge-CH 2 connectivity and germanium oxides within HM-1. However, in accordance with the 13 C{ 1 H} CP-MAS NMR data, we suggest that thermally induced TP of the germylenes provides hybrid materials consisting of germanium oxide incorporated in a phenolic resins, which contains small portions of Ge-CH 2 connectivity.…”