Understanding interactions between manganese oxide and gold that lead to enhanced activity for electrocatalytic water oxidation.

To develop active nonprecious metal-based electrocatalysts for the oxygen evolution reaction (OER), a limiting reaction in several emerging renewable energy technologies, a deeper understanding of the activity of the first row transition metal oxides is needed. Previous studies of these catalysts have reported conflicting results on the influence of noble metal supports on the OER activity of the transition metal oxides. Our study aims to clarify the interactions between a transition metal oxide catalyst and its metal support in turning over this reaction.

Interfacial alloy hydride destabilization in Mg/Pd thin films.

Recently, a large increase in the equilibrium hydrogen pressure has been reported for MG thin films capped with a Pd layer. We show that this increase is due to intermixing of Mg and Pd, as opposed to a strain effect as previously claimed. Transmission electron microscopy and depth profiling x-ray photoemission spectroscopy are used to directly measure interfacial intermixing between Mg and Pd, and we find that intermixing and equilibrium hydrogen pressure both increase with annealing.

Plasmon enhanced solar-to-fuel energy conversion.

Future generations of photoelectrodes for solar fuel generation must employ inexpensive, earth-abundant absorber materials in order to provide a large-scale source of clean energy. These materials tend to have poor electrical transport properties and exhibit carrier diffusion lengths which are significantly shorter than the absorption depth of light. As a result, many photoexcited carriers are generated too far from a reactive surface and recombine instead of participating in solar-to-fuel conversion.

Engineering light absorption in semiconductor nanowire devices.

The use of quantum and photon confinement has enabled a true revolution in the development of high-performance semiconductor materials and devices. Harnessing these powerful physical effects relies on an ability to design and fashion structures at length scales comparable to the wavelength of electrons (approximately 1 nm) or photons (approximately 1 microm). Unfortunately, many practical optoelectronic devices exhibit intermediate sizes where resonant enhancement effects seem to be insignificant.

Hydrogen storage in Pd nanodisks characterized with a novel nanoplasmonic sensing scheme.

A novel nanoplasmonic sensing scheme is introduced based on remote real-time detection of induced electronic and shape/structural changes in a metal nanoparticle during the metal-hydride formation process. The localized surface plasmon resonance (LSPR) of the nanoparticle is utilized as signal transducer for optical readout. As a model system, hydrogen storage through metal-hydride formation is studied in Pd nanodisks.