Overcoming Challenges Associated with the Analysis of Nacre by Atom Probe Tomography. Issue 3 (23rd June 2019)

• Record Type: Journal Article
• Authors: Eder, Katja; Otter, Laura M.; Yang, Limei; Jacob, Dorrit E.; Cairney, Julie M.
• Is Part Of: Geostandards and geoanalytical research. Volume 43:Issue 3(2019)
• Page Start: 385
• Page End: 395
• Publication Date: 2019-06-23
• Subjects: biomineral -- atom probe tomography -- sample preparation -- electron microscopy -- focused ion beam; Analytical geochemistry -- Periodicals; Géochimie analytique -- Périodiques; 551.9
• DOI: 10.1111/ggr.12279
• Languages: English
• ISSNs: 1639-4488

Abstract

Abstract : In this study atom probe tomography was used to study nacre, an important biocomposite material that is challenging to prepare and analyse by atom probe and, when successful, yields data that is challenging to interpret. It was found that these challenges mainly arise from the insulating and heterogeneous nano‐scale properties of nacre. We outline our current best practice for preparing and running atom probe tips, such as using a low acceleration voltage (< 3 kV) and current (≤ 50 pA) to avoid damage to the microstructure, and using transmission electron microscopy to confirm that the region of interest is located close to the apex of the atom probe tip. Optimisation of the preparation parameters led to several successful atom probe experiments, with one of the data sets containing part of an organic membrane and others showing organic inclusions within the reconstruction. Key Points: Nacre (mother‐of‐pearl) was prepared using Focused Ion Beam and analysed by atom probe tomography (APT). Experiments and sample preparation were challenging, and mitigation strategies are discussed. Successful APT experiments depend more on the quality of sample preparation and the composition/ nanostructure of the material, than on the experimental operating parameters.