am9b20653_si_001.pdf (4 MB)
Nonwetting Behavior of Al–Co Quasicrystalline Approximants Owing to Their Unique Electronic Structures
journal contribution
posted on 2020-03-20, 17:47 authored by Kanika Anand, Vincent Fournée, Geoffroy Prévot, Julian Ledieu, Émilie GaudryGood
wetting is generally observed for liquid metals on metallic
substrates, while poor wetting usually occurs for metals on insulating
oxides. In this work, we report unexpected large contact angles for
lead on two metallic approximants to decagonal quasicrystals, namely,
Al5Co2 and Al13Co4. Intrinsic
surface wettability is predicted from first principles, using a thermodynamic
model based on the Young equation, and validated by the good agreement
with experimental measurements performed under ultra-high vacuum by
scanning electron microscopy. The atomistic details of the atomic and electronic structures at
the Pb-substrate interface, and the comparison with Pb(111)/Al(111),
underline the influence of the specific electronic structures of quasicrystalline
approximants on wetting. Our work suggests a possible correlation
of the contact angles with the density of states at the Fermi energy
and paves the way for a better fundamental understanding of wettability
on intermetallic substrates, which has potential consequences in several
applications such as supported catalysts, protective coatings, or
crystal growth.