Harry Barkus Gray, PhD
21st Century Solar Army
California Institute of Technology
The sun is a boundless source of clean energy, but it goes down every night. We and many others are trying to design solar-driven molecular machines that could be used on a global scale to store solar energy by splitting water into its elemental components, hydrogen and oxygen. Hydrogen is a clean fuel that could be used directly or combined with carbon dioxide to produce methanol, a liquid fuel. We are investigating the structures and mechanisms of hydrogen evolving catalysts made from Earth abundant elements such as cobalt, iron, nickel, and molybdenum. We also are employing pulsed laser ablation for synthesis of metaloxide nanoparticles that will be deployed as catalysts on photoanodes such as tungsten oxide. To aid our research, we have recruited hundreds of students to join a Solar Army whose mission is the discovery of mixedmetal oxides for testing on the photoanodes of our solar water splitters.
Harry Gray is the Arnold O. Beckman Professor of Chemistry and the Founding Director of the Beckman Institute at the California Institute of Technology. After graduate work in inorganic chemistry at Northwestern University and postdoctoral research at the University of Copenhagen, he joined the chemistry faculty at Columbia University, where in the early 1960s he developed ligand field theory to interpret the electronic structures and reactions of transition metal complexes. After moving to Caltech in 1966, he began work in biological inorganic chemistry and inorganic photochemistry that led to the development of molecular systems for the storage of solar energy. During investigations of metalloprotein redox reactions in the 1980s, he demonstrated that electrons can tunnel rapidly over long molecular distances through folded polypeptide structures. This discovery opened the way for experimental and theoretical work that shed new light on the mechanisms of electron flow through proteins that function in respiration and photosynthesis.
Gray has published over 850 research papers and 18 books. He has received the National Medal of Science from President Ronald Reagan (1986); the Pauling Medal (1986); the Linderstrøm-Lang Prize (1992); the Gibbs Medal (1992); the Harvey Prize (2000); the Nichols Medal (2003); the National Academy of Sciences Award in Chemical Sciences (2003); the Benjamin Franklin Medal in Chemistry (2004); the Wolf Prize in Chemistry (2004); the City of Florence Prize in Molecular Sciences (2006); the Welch Award in Chemistry (2009); the Japan International Coordination Chemistry Award (2010); the Othmer Gold Medal (2013); six national awards from the American Chemical Society, including the Priestley Medal (1991); and 18 honorary doctorates, including ones from Rochester, Northwestern, Pennsylvania, Chicago, Columbia, Toulouse, Florence, Copenhagen, Edinburgh, and the Weizmann Institute of Science. He is a member of the National Academy of Sciences; the American Academy of Arts and Sciences; the American Philosophical Society; a foreign member of the Royal Danish Academy of Sciences and Letters; the Royal Swedish Academy of Sciences; the Royal Society of Great Britain; and the Accademia Nazionale dei Lincei. He is a Director of University Science Books and Chair of the Board of Directors of the Arnold and Mabel Beckman Foundation.