TY - JOUR A1 - Lippitz, Andreas A1 - Unger, Wolfgang A1 - Boese, O. A1 - Kemnitz, E. T1 - y-Al2O3 by Au 4f7/2-referenced XPS and XAES N2 - Powder x-ray diffraction (XRD) defined -Al2O3 has been investigated by x-ray photoelectron spectroscopy (XPS) and x-ray excited Auger electron spectroscopy (XAES). The Au 4f7/2 orbital is used for static charge referencing. This feature originates from well-defined and chemically inert 20 nm highly dispersed gold particles deposited on the sample surface. The particles, with a narrow particle size distribution, were obtained from a highly purified colloidal solution (sodium concentration below 1 mg/l). This procedure allows a determination of gold-referenced XPS and XAES data sets. ©2001 American Vacuum Society. KW - Au 4f referenced XPS data KW - Aluminium KW - Oxide PY - 2001 UR - http://scitation.aip.org/vsearch/servlet/VerityServlet?KEY=SSSPEN&ONLINE=YES&smode=strresults&sort=chron&maxdisp=25&threshold=0&possible1zone=article&possible4=lippitz&possible4zone=author&bool4=and&fromyear=2001&OUTLOG=NO&viewabs=SSSPEN&key=DISPLAY&docID DO - https://doi.org/10.1116/11.20020305 SN - 1055-5269 SN - 1520-8575 VL - 8 IS - 1-4 SP - 214 EP - 219 PB - AIP CY - Woodbury, NY AN - OPUS4-1910 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grohmann, I. A1 - Kemnitz, E. A1 - Lippitz, Andreas A1 - Unger, Wolfgang T1 - Curve Fitting of Cr2p Photoelectron Spectra of Cr2O3 and CrF3 KW - Photoelektronenspektroskopie KW - Kurvenglättung KW - Chrom PY - 1995 SN - 0142-2421 SN - 1096-9918 VL - 23 SP - 887 EP - 891 PB - Wiley CY - Chichester AN - OPUS4-678 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Grohmann, I. A1 - Hess, A. A1 - Kemnitz, E. A1 - Frentrup, W. A1 - Unger, Wolfgang T1 - XANES-Investigations of coprecipitated AIF3/MgF2 phases KW - XANES-Spektrum KW - Kalzienieren KW - Magnesium PY - 1996 SN - 0179-4159 SP - 222 EP - 223 PB - Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung CY - Berlin AN - OPUS4-682 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Anja A1 - Krahl, T. A1 - Radnik, Jörg A1 - Wagner, Andreas A1 - Werner, W. S. M. A1 - Ritter, B. A1 - Kemnitz, E. A1 - Unger, Wolfgang T1 - Chemical in-depth analysis of (Ca/Sr)F2 core–shell like nanoparticles by X-ray photoelectron spectroscopy with tunable excitation energy N2 - The fluorolytic sol–gel synthesis is applied with the intention to obtain two different types of core–shell nanoparticles, namely, SrF2–CaF2 and CaF2–SrF2. In two separate fluorination steps for core and shell formation, the corresponding metal lactates are reacted with anhydrous HF in ethylene glycol. Scanning transmission electron microscopy (STEM) and dynamic light scattering (DLS) confirm the formation of particles with mean dimensions between 6.4 and 11.5 nm. The overall chemical composition of the particles during the different reaction steps is monitored by quantitative Al Kα excitation X-ray photoelectron spectroscopy (XPS). Here, the formation of stoichiometric metal fluorides (MF2) is confirmed, both for the core and the final core–shell particles. Furthermore, an in-depth analysis by synchrotron radiation XPS (SR-XPS) with tunable excitation energy is performed to confirm the core–Shell character of the nanoparticles. Additionally, Ca2p/Sr3d XPS intensity ratio in-Depth profiles are simulated using the software Simulation of Electron Spectra for Surface Analysis (SESSA). In principle, core–shell like particle morphologies are formed but without a sharp interface between calcium and strontium containing phases. Surprisingly, the in-depth chemical distribution of the two types of nanoparticles is equal within the error of the experiment. Both comprise a SrF2-rich core domain and CaF2-rich shell domain with an intermixing zone between them. Consequently, the internal morphology of the final nanoparticles seems to be independent from the synthesis chronology. KW - Metal fluorides KW - Sol-gel synthesis KW - Synchrotron radiation KW - X-ray photoelectron spectroscopy PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-522284 DO - https://doi.org/10.1002/sia.6937 SN - 0142-2421 VL - 53 IS - 5 SP - 494 EP - 508 PB - Wiley VCH AN - OPUS4-52228 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -