Simulation of the LMM auger spectra of copper

Abstract

Quantitative Auger analysis is much more difficult to achieve than quantitative XPS, as the latter shows only one photoelectron peak when the former exhibits many relaxation peaks laying over a 100 ev range. A good way to check our understanding of the Auger process is to simulate spectra. For that we need to get an estimation of (i) the ionization probability and its variation with depth, (ii) the contribution of each ionization and relaxation processes, and (iii) the type of interaction between electron and solid. As the phenomena are basically the same for the transport of Auger electrons as for primary electrons, we used the same physical parameters and simulation models (layer by layer and Monte Carlo) as we previously used for the determination of the background in copper. A comparison between calculated and experimental results is presented.

Unveiling the Activity Origin of a Copper‐based Electrocatalyst for Selective Nitrate Reduction to Ammonia

“…On the contrary, the Auger peak of Cu + in the Cu/Cu 2 O NWAs shifts to higher binding energy by 0.3 eV compared to pure Cu 2 O NWAs (Figure e; Supporting Information, Figure S20). The AES results indicated the electron transfer from Cu 2 O to Cu at the interface of Cu/Cu 2 O NWAs . Furthermore, the simulated schematic diagram in Figure f also exhibited the extra electron density of Cu in Cu/Cu 2 O NWAs compared with bare Cu.…”

“…The AES results indicated the electron transfer from Cu 2 O to Cu at the interface of Cu/Cu 2 O NWAs. [41] Furthermore, the simulated schematic diagram in Figure 5 f also exhibited the extra electron density of Cu in Cu/Cu 2 O NWAs compared with bare Cu. The model showed the electron density of Cu in Cu/Cu 2 O NWAs minus the electron density of Cu in pure Cu NWAs, and the extra electronic cloud was the yellow part.…”

Pyrrolidone ligand improved Cu‐based catalysts with high performance for acetylene hydrochlorination

“…[ 42 ] Figure 8c,d showed the curves in the Cu LMM Auger spectra. In the peak fit of Cu LMM, three different peaks could be fitted including one main peak with a kinetic energy of 915.2 eV assigned to Cu + species, two small peaks at around 918.4 and 910.0 eV attributed to the Cu 0 species and a different Cu transition state, [ 43 ] respectively.…”

Observation of Non‐FCC Copper in Alkynyl‐Protected Cu53Nanoclusters

“…In the Cu LMM Auger spectrum, there is a major component at 570.49 eV related to Cu I species and a shoulder at 568.0 eV for Cu 0 . The other peak at 573.2 eV might represent the 1 S state of L 3 M 45 M 45 relaxations (Supporting Information, Figure S18) . The bonding of Cu with these ligands also caused a slight Cu 2p 3/2 binding energy shift towards higher value (933.0 eV) in comparison with 932.6 eV for Cu foil (Figure D).…”

“…In the Cu LMM Auger spectrum, there is amajor component at 570.49 eV related to Cu I species and ashoulder at 568.0 eV for Cu 0 .The other peak at 573.2 eV might represent the 1 Ss tate of L 3 M 45 M 45 relaxations (Supporting Information, Figure S18). [43] The bonding of Cu with these ligands also caused as light Cu 2p 3/ 2 binding energy shift towards higher value (933.0 eV) in comparison with 932.6 eV for Cu foil ( Figure 4D). Theabove results corroborate the view that Cu II ions successively coordinated with the introduced ligands and changed to Cu I .F urther adding NaBH 4 led to partial reduction of Cu I species and the generation of Cu 53 eventually.…”