Advanced analysis of copper X‐ray photoelectron spectra

Abstract

Chemical state X‐ray photoelectron spectroscopic analysis of copper species is challenging because of the complexity of the 2p spectra resulting from shake‐up structures for Cu(II) species and overlapping binding energies for Cu metal and Cu(I) species. This paper builds upon and extends previously published X‐ray photoelectron spectroscopy curve‐fitting and data analysis procedures for a wide range of copper containing species. Steps undertaken include the following: (i) an examination of existing Cu 2p 3/2 main peak and Cu 2p 3/2 – Cu L 3 M 4,5 M 4,5 Auger parameter literature data, (ii) analysis of a series of quality standard samples, (iii) curve‐fitting procedures for both the Cu 2p 3/2 and the Cu L 3 M 4,5 M 4,5 spectra (as well as associated anions), (iv) calculations that determine the amount of Cu(II) species in a mixed oxidation state system, (v) calculations and necessary data for thin film mixed oxide/hydroxide thickness measurements, and (vi) a presentation of literature and standard sample values in a Wagner (chemical state) plot. Copyright © 2017 John Wiley & Sons, Ltd.