Nanocatalysis
Catalysis becomes extremely complex at nanoscale. The goal of this work is to understand
the catalytic behavior of metal-oxide supported nanoparticles under realistic experimental
conditions. We elucidate the bonding characteristics of adsorbates on nanoparticles and
develop relationships predicting their binding energy versus the nanoparticle structural
characteristics. Additionally, we investigate the catalytic mechanisms on both metals and
metal oxide supports by taking into account complex physical phenomena (support effects and
reconstruction) occurring on the catalyst. Finally, we propose novel nanocatalysts with
optimal catalytic activity under experimental conditions. Applications include enviromental
catalysis and mitigation of greenhouse gases concentration.
Electrochemical Hydrogen Production
Reducible transition metal oxides are dynamic, non-proton-blocking electrocatalysts for the
hydrogen evolution reaction (HER). While pristine oxides often lack inherent activity,
cathodic polarization drives proton-insertion coupled electron transfer, transforming
the material into a highly active hydrogen bronze. This bulk intercalation alters the
oxide's electronic structure, activating surface metal sites and preventing water-induced
deactivation. Furthermore, the bulk lattice acts as a proton reservoir, enabling inserted
protons to diffuse and directly participate in H
2 generation. The efficiency
and thermodynamics of this process are highly tunable through structural symmetry, hydration
and heteroatom doping.
Biomass Conversion
Dehydration reactions are the most important reactions for converting biomass to fuels and
chemicals. A fundamental understanding of the dehydration mechanisms can help us elucidate
and eventually control the selective dehydration of complicated biomass molecules, such as
polyols, to value-added chemicals. In this work, we investigate the dehydration of simple
alcohols on various metal-oxides in the presence of water. We develop dehydration
relationships as a function of the metal-oxide acidity and the alcohols properties, aiming
to predict the dehydration behavior of polyols on different oxides.
Nanoparticle Growth
The nanoparticle properties are directly related to their structural characteristics. Even
though nanoparticles of different sizes and morphologies can be synthesized in the lab, their
growth mechanisms are completely unknown. Here, we investigate the colloidal nanoparticle
growth in the presence of solvents and capping agents. We provide insights into the
nanoparticle growth mechanisms and propose design guidelines to control nanoparticle
characteristics (size, shape, dispersity) during synthesis.