University of Oregon chemists say that ultra-thin films of nickel and iron oxides made through a solution synthesis process are promising catalysts to combine with semiconductors to make devices that capture sunlight and convert water into hydrogen and oxygen gases.
Researchers in the Solar Materials and Electrochemistry Laboratory of Shannon Boettcher, professor of chemistry, studied the catalyst material and also developed a computer model for applying catalyst thin films in solar water-splitting devices as a tool to predict the effectiveness of a wide range of catalyst materials for solar-hydrogen production.
The project has resulted in two recent papers.
The first, detailed last September in the Journal of the American Chemical Society, showed that films of a nickel-iron mixed oxide with an atomic structure similar to naturally occurring minerals show the highest catalytic activity for forming oxygen from water, based on a side-by-side comparison of eight oxide-based materials targeted in various research efforts.
The second paper, just published in the Journal of Physical Chemistry Letters, details the performance of the catalyst thin films when combined with semiconductor light absorbers, showing that the nickel-iron oxide catalyst was most effective with a film just 0.4 nanometers thick.
Boettcher’s lab, located in the UO’s Materials Science Institute, studies fundamental materials chemistry and physical concepts related to the conversion of solar photons (sunlight) into electrons and holes in semiconductors that can then be used to drive chemical processes such as splitting protons off water to make hydrogen and oxygen gases. Multiple labs across the country are seeking effective and economical ways of taking sunlight and directly producing hydrogen gas as an alternative sustainable fuel to replace fossil fuels.
Source: Science Daily