UC Santa Barbara

A great deal of scientific research in recent decades has been focused on bringing new

and more efficient forms of solar energy to market, as well as making existing solar energy

technology more viable. Two of the central issues in this research have been energy stor-

age, to account for the discrepancy between hours peak production and hours of usage,

and the efficiency of photovoltaic devices. Coming from an infrastructure built off of

burning chemical fuels, storing solar energy in chemical bonds to make so-called ’solar

fuels’ has been one of the major area of research. This involves both photovoltaic and

electrocatalytic aspects, which can be incorporated into single devices or implemented

separately with a discrete photovoltaic driving an electrochemical reaction. We have

used in-operando Raman spectroscopy to to improve understanding of a popular anode

material for the splitting of water, Manganese Oxide, as it undergoes structural changes

during operation; with implications for the production of more efficient anodes.

Further, we have the sought to improve the functionality of existing materials by

the use of oscillations of electrons in metal nanostructures. The collective oscillations of

conduction electrons at the surface of metals, called surface plasmons, induce an electric

field in surrounding dielectric materials called the surface plasmon polariton. This can be

tuned by manipulation of the structure of the metal on the length scale of the mean free

path of electrons in the metal. By careful manipulation of noble metal nanostructures, we have been able to manipulate the properties of semiconductor electrodes - shifting

the product distribution of CO2 reduction on Cu2 O. Additionally, we have been able

to use plasmonic nanoparticles to make pan-chromatic light aborbers for photovoltaic

applications.