Atomic Structure, Dynamics, Scale-up and Catalytic Applications of Deposited Nanoclusters

Size-selected nanoparticles (atomic clusters), deposited onto supports from the beam in the absence of solvents, represent a new class of model systems for catalysis research and potentially small-scale industrial manufacturing of selective catalysts. To translate these novel and well-controlled systems into practical use, two major challenges have to be addressed.(1) Very rarely have the actual structures of clusters been obtained from direct experimental measurements, so the metrology of these new material systems has to improve. The availability of aberration-corrected HAADF STEM is transforming our approach to this structure challenge [1,2]. I will address the atomic structures of size-selected Au clusters, deposited onto standard carbon TEM supports from a mass-selected cluster beam source. (2) A second major challenge is scale-up, needed to enable the beautiful physics and chemistry of clusters to be exploited in applications, notably catalysis [4]. In an effort to address this scale-up challenge, I will discuss the development of a new kind of nanoparticle source, the “Matrix Assembly Cluster Source” (MACS) [4-6]. [1] Z.Y. Li et al, Nature 451 46 (2008).[2] Z.W. Wang and R.E. Palmer, Phys. Rev. Lett. 108 245502 (2012).[3] P.R. Ellis et al, Faraday Discussions 188 39 (2016).[4] R.E. Palmer et al. Acc. Chem. Res. 51 2296 (2018).[5] R.E. Palmer, L. Cao and F. Yin, Rev. Sci. Instrum. 87 046103 (2016).