Researchers at The University of Texas at Austin have received about $2.5 million to identify new materials that will efficiently absorb sunlight and split water (H2O) into clean hydrogen fuel, which could power cars and be used to generate electricity.
For the next three years, chemical engineering Professor Charles Mullins, chemistry Professor Allen Bard and mathematics Professor Irene M. Gamba will collaborate on the endeavor, which encompasses two grants from the National Science Foundation ($1.4 million) and the U.S. Department of Energy (about $1.1 million). Bard and Mullins are affiliated with the Center for Electrochemistry at the university.
The center is a multi-faculty collaboration devoted to research on fundamental and applied aspects of electrochemistry, which has already received research support for work on electrochemical energy sources such as batteries and fuel cells, solar energy research and new materials.
"Sustainable energy ultimately will involve the conversion of solar energy economically and efficiently to chemical fuels and electricity," Bard said. "Our work focuses on discovering new materials for this and obtaining a better understanding of how their composition and structure govern their behavior."
Mullins added, "The grants will fund us to explore finding new materials that will efficiently absorb sunlight and drive chemical reactions to break water into hydrogen (a fuel) and oxygen. These materials also need to be cheap and composed of elements that are abundant."
The researchers will be examining novel metal oxides (variations of more common ones like titanium dioxide and iron oxide), which can act as semiconductors.
Mullins said because sunlight and water are relatively inexpensive and plentiful starting points, the hydrogen fuel produced by an efficient process would also be cheap.
"Plus, it would be a sustainable form of energy," he said. "And energy, of course, is a terribly important problem that we are currently facing."
Mullins said that researchers have studied water splitting using photoelectrochemistry for the past 40 years and progress has been made. However, efficient, cheap and abundant materials have yet to be discovered to make solar water splitting a viable process.
He said Bard will use a "combinatorial" approach for rapidly making complex compositions of metal oxides and testing them for their promise as photoelectrocatalysts, the material that facilitates the split.
"Once promising materials have been identified, we'll research how to create nano-scale structures of that material that enhance the intrinsic properties of the material for light-absorption and water-splitting chemistry," Mullins said.
Gamba's past work in the mathematical treatment of electron and hole transport in semiconductors makes her essential to establishing useful theoretical models for these systems.
Mullins holds the Z.D. Bonner Professorship in Chemical Engineering, Bard holds the Hackerman-Welch Chair in Chemistry, and Gamba holds the Joe B. and Louise Cook Professorship in Mathematics.