We
report the preparation of discrete nanometer-scale zinc-based
clusters and use them to form sub-15 nm structures by means of extreme
ultraviolet lithography. By taking advantage of a metal-containing
building unit derived by a metal–organic frameworkMOF-2,
we found the 3-methyl-phenyl-modified Zn-mTA cluster
that formed is well-defined with controlled size and structure and
demonstrates extremely high solubility. Progress in recent years in
metal–organic frameworks has created a rich variety of metal-containing
structures that are useful for numerous applications. Substitution
of the bridging ligands with monovalent ligands produces a discrete
metal–organic cluster that strongly interacts with soft X-rays
at a wavelength of 13 nm. Here we describe the design, preparation,
computational modeling, and physical characterization of these new
materials. Such metal-containing structures may form the basis of
photoresists that enable the next generation of microelectronic devices.
Polybenzimidazole (PBI)-based membranes
are one of the systems
of choice for polymer electrolyte fuel cells. Monomer sulphonation
is one of the strategies suggested to improve proton transport in
these membranes. We report a NMR and dynamic mechanical study aiming
to investigate the effect of the sulphonation on the proton dynamics
and the mechanical properties of the membranes. The analyses of 1H self-diffusion coefficients and 1H and 31P spectra versus temperature show that sulphonation causes the formation
of interchain cross-links, which involve phosphoric acid molecules
and the sulfonic groups. This, in turn, reduces the proton mobility
and, consequently, the ionic conductivity. The increase of the membrane
stiffness with sulphonation is confirmed by dynamic mechanical analysis
through the behavior of the storage modulus.
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