Speaker
Description
Beam deposition of mass-selected bimetallic clusters produced in a laser ablation source provides a powerful platform to investigate cluster–surface interactions and to establish structure–activity relationships in well-defined catalytic systems. The combination of controlled gas-phase growth, soft landing, and detailed post-deposition characterization enables systematic studies of structural, chemical, and electronic properties of supported nanoalloys before, during, and after reaction.
Deposition of gas-phase produced Au$_x$Cu$_{1−x}$ clusters ($x$ = 1, 0.75, 0.5, 0.25 and 0) onto TiO$_2$ nanotubes was found to significantly enhance photoelectrochemical water splitting. Detailed structural and chemical analysis reveals segregation-driven formation of bifunctional catalytic sites composed of metallic Au/AuCu domains in contact with a copper oxide surface layer. These findings highlight how cluster composition and restructuring upon deposition determine interfacial properties and catalytic performance [1].
To bridge cluster-based model studies and realistic catalytic environments, a dedicated microreactor was developed to probe minute quantities of beam-deposited nanoparticles under elevated pressures (up to 40 bar) and temperatures (up to 250 °C). PdZnO$_x$ and CuZnO$_x$ clusters soft-landed on oxide and carbon supports were investigated for CO$_2$ hydrogenation via the reverse water–gas shift reaction [2] and methanol synthesis [3]. By tuning alloying and oxidation during cluster growth through the aggregation atmosphere, catalytic activity and selectivity could be controlled.
These results demonstrate how cluster beam deposition links gas-phase nanoalloy formation with surface-supported functionality, providing insight into alloying, segregation, metal–support interactions, and their impact on catalytic performance.
[1] V.C. Chinnabathini, K.R. Ag, T.H.T. Nguyen, Z. Zarkua, I. Abbas, T.H. Hoang, P. Lievens, D. Grandjean, S.W. Verbruggen, E. Janssens, Nanoscale 17, 833 (2025).
[2] I. Abbas, F. Romeggio, K. Pilarczyk, S. Kuhn, C.D. Damsgaard, J. Kibsgaard, P. Lievensa, D. Grandjean, E. Janssens, Chem. Eng. J. 503, 158127 (2025).
[3] I. Abbas, W. Ji, et al., in preparation (2026)