Cryo Atom Probe: Freezing atoms in place for 3D mapping

Preparation of atom probe tips from (nano)particles in dispersion using (di)electrophoresis and electroplating

“…for APT specimens are still not established. There are few reports described in the literature (Chen et al, 2021;Schreiber et al, 2018), and often expensive hardware is needed (Perea, 2020). By avoiding this preparation step, we enable the preparation of particles for APT without an established cryo lift-out procedure.…”

“…Even though progresses in the area of cryo lift‐outs of TEM lamellas are reported in literature (Kuba et al, 2021; Parmenter & Nizamudeen, 2021; Schaffer et al, 2019), cryo lift‐outs for APT specimens are still not established. There are few reports described in the literature (Chen et al, 2021; Schreiber et al, 2018), and often expensive hardware is needed (Perea, 2020). By avoiding this preparation step, we enable the preparation of particles for APT without an established cryo lift‐out procedure.…”

Atom Probe Study of 1-Octadecanethiol Self-Assembled Monolayers on Platinum (111) and (200) Surfaces

“…The particular goal of this study is to investigate whether the size of the evaporated fragments can be influenced by variation of the laser energy. Biological and organic materials are on the rise in the atom probe community and thanks to the developments of FIB cryo-preparation techniques (Gerstl & Wepf, 2015; Gerstl et al, 2017; Cairney et al, 2019; El-Zoka et al, 2020; Schwarz et al, 2020; Chen et al, 2021; Stender et al, 2021), even room temperature liquids are becoming accessible. In view of the typically obtained complex mass spectra with many different molecular fragments, even from simple hydrocarbon systems, it is crucial to understand which conditions yield which kind of molecular ions.…”

Nanoporous metal tips as frameworks for analysing frozen liquids with atom probe tomography

“…The tip is then dealloyed using an acid which attacks metal A but not metal B. The nanoporous tip is then immersed in the sample solution, allowing the liquid to intercalate into the pores, before being plunge-frozen in liquid nitrogen or ethane and transferred to cryogenic vacuum storage [3,7] for analysis.…”

“…However, this powerful technique has historically been limited to dense, conductive solids due to the stringent specimen geometry requirements [1][2][3]. Developing a workflow that enables the analysis of liquids and soft matter is one of the next big frontiers for translating the technique to wider materials science applications [3], and several groups have recently reported progress in this area [4][5][6][7]. Examples include the deposition of liquids and polymers onto metal tips [8,9], encapsulating aqueous solutions using graphene [10], using focused ion beam (FIB) milling and lift-out to observe water-glass interfaces [11,12], and using a FIB to mill water which has been cast and frozen on nanoporous gold [13] or microstructured tungsten [14].…”