Role of Defects in Atom Probe Analysis of Sol-Gel Silica
Journal article, 2025
Silicon dioxide is a suitable material to encapsulate proteins at room temperature so that they can be analyzed at the atomic level using laser-assisted atom probe tomography (La-APT). To achieve this goal, in this study we show that UV and deep-UV lasers can achieve a high success rate in La-APT of silica in terms of chemical resolution and three-dimensional image volume, with both lasers providing comparable results. Since the La-APT analyses are driven by photon absorption, in order to understand the mechanisms behind the enhanced absorption of UV light, we performed density functional theory calculations to model the electronic and optical properties of amorphous silica matrices generated using a Monte Carlo approach to structural optimization. In particular, we have investigated the role of various defects introduced during sample preparation, such as substitutional and interstitial carbon, sodium and gallium ions, and hydrogen. Our results show that the presence of defects increases the absorption of silica in the UV and deep-UV range and thus improves the La-APT capabilities of the material. However, due to the low density of free charge carriers resulting from the absorption of laser energy by defects, deviations from the nominal chemical composition and suboptimal chemical resolution may occur, potentially limiting the optimal acquisition of APT mass spectra.
Author
Gustav Eriksson
Applied Chemistry 3.4
Matteo De Tullio
Institute for Research and Innovation in Biomedicine
Francesco Carnovale
University of Trento
National Institute for Nuclear Physics
Fondazione Bruno Kessler (FBK)
Giovanni Novi Inverardi
University of Trento
National Institute for Nuclear Physics
Fondazione Bruno Kessler (FBK)
Tommaso Morresi
Fondazione Bruno Kessler (FBK)
National Institute for Nuclear Physics
Jonathan Houard
Institute for Research and Innovation in Biomedicine
Marc Ropitaux
Institute for Research and Innovation in Biomedicine
Ivan Blum
Institute for Research and Innovation in Biomedicine
Emmanuel Cadel
Institute for Research and Innovation in Biomedicine
Gianluca Lattanzi
University of Trento
National Institute for Nuclear Physics
Mattias Thuvander
Chalmers, Physics, Microstructure Physics
Martin Andersson
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Mats Hulander
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Simone Taioli
National Institute for Nuclear Physics
Fondazione Bruno Kessler (FBK)
Angela Vella
Institute for Research and Innovation in Biomedicine
ACS Omega
24701343 (eISSN)
Vol. 10 30 33741-33754Subject Categories (SSIF 2025)
Atom and Molecular Physics and Optics
DOI
10.1021/acsomega.5c04733