Rhodium and Rhodium Oxide Thin Films Characterized by XPS

Abstract

RhO2 belongs to the family of conducting platinum group metal oxides, which have attracted attention as new capacitor electrode materials for dynamic random access memories (DRAMs) and nonvolatile ferroelectric random access memories (FeRAMs). Rh, Rh2O3, and RhO2 thin films were prepared by sputtering and their XPS spectra were collected with a monochromatic Al Kα x-ray source. This report includes XPS spectra of Rh 3d and O 1s core regions for these films.

Adsorbate-induced structural evolution changes the mechanism of CO oxidation on a Rh/Fe3O4(001) model catalyst

“…We also observe a strong positive binding energy shift in the Rh 3d XPS peak maximum (Fig. 4c) after O 2 dosing at 60 K (308.6 eV), which shifts further to ≈309.0 eV upon heating above 250 K. Even though the position observed at 60 K is already close to that expected for RhO 2 (308.6 eV) 34 or Rh 2 O 3 (308.3 eV), 34,35 and thus could be already interpreted as a signal corresponding to the oxidised Rh clusters, the further shift above 250 K accompanied with the disappearance of the superoxo component in the O 1s region suggests that the agglomeration takes place between 100 K and 250 K, and the O 1s signal of the resulting Rh x O y nanoparticles is indistinguishable from that of the O 2− in the Fe 3 O 4 support.…”

Electronic Structure Evolution with Composition Alteration of RhxCuy Alloy Nanoparticles

“…The binding energies (BEs) of Rh 3 d and Cu 2 p 3/2 for mono- and bimetallic alloy NPs and reference metals are summarised in Table 1. The peak positions and their assignments are consistent with reported data23242526272829. It should be mentioned that, within the standard deviation of transmission electron microscopy (TEM) results (refer to Supplementary Figure SI 1), the size of NPs discussed here can be regarded as similar.…”

“…With increasing Cu content of the bimetallic alloy NPs, the main peak position recovers to that of Rh 0 , indicating intermetallic charge transfer from Cu to Rh in the alloy NPs. The main peak positions for Rh reference are consistent with the Rh 0 BE reported elsewhere23242526.…”

Surface modification of hematite photoanode films with rhodium

“…In Fig. 2, the Rh3d 5/2 peak is 309.5 eV, much higher than the reported values for Rh 2 O 3 (308.4 eV [22], 308.3 eV [23]). Close examination of Rh3d 5/2 orbit was carried out through peak fitting analysis (see the inset of Fig.…”