Ion beam analysis and modification techniques for hydrogen related nanomaterials

Efficient hydrogen production and hydrogen storage in solid-state materials are among the vital challenges to implementing hydrogen-based energy technologies. Nanostructuring of the metal hydrides offers a viable solution to the challenge of H storage. Size reduction to the nanoscale level may lead to changes in enthalpy and rate of H absorption/desorption through nano-interfacial reaction pathways. Furthermore, 2D materials exhibit excellent electrocatalytic activity for hydrogen
production due to their large specific surface area as well as abundant surface functional groups. 

Materials analysis techniques based on energetic ions offer a unique set of tools for material characterization in terms of chemical composition and structure. Their sensitivity to both light and heavy chemical elements, combined with their generally non-destructive nature and robust applicability, makes them particularly well suited for investigating materials relevant to the hydrogen economy.

In the first part of this contribution, the focus is on epitaxial films of vanadium, studied as a model system of relevance for hydrogen storage. Both V and VHx thin films were characterized with a combination of real-space and reciprocal space methods. The strain, originating from the epitaxial growth, as well as induced by hydrogen, was quantified through x-ray diffraction (XRD) and time-of-flight medium energy ion scattering (ToF-MEIS), taking advantage of the blocking
effect (see Figure 1)¹. Hydrogen, introduced via thermal loading and/or ion implantation, was quantified using nuclear reaction analysis (NRA), while its lattice site-location was determined from channeling experiments compared with Monte Carlo simulations².

Complementing the characterization studies, the second part of this contribution presents the development of ultra-low energy ion beam system designed for modification of thin films and 2D materials. The system was used for sub-surface implantation, while the implantation depth was verified using IBA techniques.

References
[1] D. Moldarev et al., APL Materials 13, 061118 (2025).
[2] K. Komander et al., PRL 127, 136102 (2021).