Systematic and collaborative approach to problem solving using X-ray photoelectron spectroscopy

Mark Greiner,Mireille Richard‐Plouet,Delphine Flahaut,Emily Smith,Neal Fairley,Jonas Baltrusaitis,Vincent Fernandez,John Walton,David Morgan,Sven Tougaard,Mark Biesinger,Catherine Guillot-Deudon

doi:10.1016/j.apsadv.2021.100112

Abstract

The methodology presented within this work is a result of years of interactions between many junior and senior X-ray Photoelectron Spectroscopy (XPS) users operating within the CasaXPS spectral processing and interpretation program framework. In particular, discussions arising from a series of workshops have been a significant source for developing the overall XPS data processing concept and are the motivation for creating this work. These workshops organized by the Institut des Matériaux Jean Rouxel (IMN), Nantes gather both experienced and novice users of XPS for a week of discourse in conceptual experiment design and the resulting data processing. However, the framework constructed and utilized within these workshops encouraged the dissemination of knowledge beyond XPS data analysis and emphasized the importance of a multi-disciplinary collaborative approach to surface analysis problem-solving. The material presented here embodies data treatment originating from data made available to the first CNRS Thematic Workshop presented at Roscoff 2013. The methodology described here has evolved over the subsequent workshops in 2016 and 2019 and currently represents the philosophy used in CasaXPS spectral data processing paradigm.

Highlights

X-ray Photoelectron Spectroscopy (XPS) is utilized to provide a chemical composition of complex materials that range from inorganic to biological materials under UHV conditions with recent developments in the instrumentation allowing to operate under elevated pressures or moist environments [1,2,3,4,5]
The methodology presented within this work is a result of years of interactions between many junior and senior X-ray Photoelectron Spectroscopy (XPS) users operating within the CasaXPS spectral processing and interpre tation program framework
The discussion that follows is an example analysis for molybdenum sulfate developed as part of the CasaXPS user group aimed at developing a holistic methodology for XPS analysis while calculating the amount of molybdenum measured by XPS from a particular sample

Summary

Introduction

X-ray Photoelectron Spectroscopy (XPS) is utilized to provide a chemical composition of complex materials that range from inorganic to biological materials under UHV conditions with recent developments in the instrumentation allowing to operate under elevated pressures or moist environments [1,2,3,4,5]. The discussion that follows is an example analysis for molybdenum sulfate developed as part of the CasaXPS user group aimed at developing a holistic methodology for XPS analysis while calculating the amount of molybdenum measured by XPS from a particular sample. The ad vantages of understanding the material properties of a sample are important It is, necessary to have available, persons with knowledge of both. Once XPS data are obtained, interpretation of the data is as important as the overall analysis process, and should be considered an integral part of the analysis workflow. Applied Surface Science Advances 5 (2021) 100112 to photoemission intensities are performed via Scofield cross-sections [18], National Physical Laboratory transmission correction [19], escape depth correction based on effective attenuation [20] and angular distribution correction assuming an angle between the X-ray source and the direction of collection equal to 60◦

Instrumentation

Sample knowledge

The motivation for studying “molybdenum sulfate”

Analysis of data

Use of known samples when creating peak models

Implications of the constructed model

Conclusion