A Conversation with Tom Meyer
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Alamos National Laboratory (LANL) from 2000 until 2004, it was interesting to watch much of this unfold from a broad perspective because LANL had extensive commitments to many aspects of energy research given its origin as a nuclear energy laboratory. Our own effort at UNC is based on solar energy but with a focus on solar fuels. Solar fuels have the advantage of being generated and usable as an energy source as you need it. Seeing fields of PV collectors is appealing, but what happens when the sun goes down? If the sun becomes a key, worldwide energy source, vast unmet needs for energy conversion and storage have to be met, well past the ability of current technologies. The goal of solar fuels follows from natural photosynthesis: create and use high-energy molecules on demand such as hydrogen from water splitting or carbonbased fuels from CO2. As fuels, they can be stored and used when needed, compatible with existing technologies. EL: Despite four decades of research, solar f uels production (photocatalytic hydrogen production and CO2 reduction) has yet to make a major impact in terms of practical devices. In your opinion, what efforts are needed to overcome the barrier of catalyst development and reactor design? Meyer: Just keep supporting basic research. The problems are difficult with major challenges to overcome. I look back at our work, that began in the 1970s, and reflect on how much we have accomplished in a short period of time based on our current ERFC funding, which began in 2008. Back in the 1970s there were no catalysts for water splitting or CO2 reduction. Semiconductor science was in its infancy, and there were no well-established protocols for how to proceed. There was a national interest in energy research, based on an Arab oil embargo, but Reagan became president and funding disappeared. Here we are, 40 years later, with adequate funding in place for the first time through the EFRC. With available funding, it has been possible, for the first time, to attract a set of students, postdocs, and faculty needed to implement a broadly based research effort at appropriate levels by combining synthesis, catalysis, spectroscopy, semiconductors, and device design at levels sufficient to move the area forward in a significant way. It is a brave new world with high levels of integration from synthesis to device design required for success. From the beginning, the Center has adopted and used a high-level management plan that features key faculty and, most of all, talented students and postdocs who have worked together across science boundaries to make things happen. EL: Many young researchers aspire to engage in energy research. What advice can you give them on how to become a successf ul researcher? Meyer: Given the times, a good choice. The world can use well-trained people dedicated to constructing a new world
rof. Thomas (Tom) Meyer is a leading researcher in the field of solar photochemistry. Since the early days of his research career in the 1970s he has been actively involved in studying excited-state properties of inorganic complexes with implications for artificial photosynthesis. Notably, his pioneering work on developing molecular catalysts for water oxidation and CO2 reduction has provided the basis for implementing new approaches to artificial photosynthesis. Every year I have the opportunity to meet with Prof. Meyer at the annual DOE Solar Photochemistry Research Conference and discuss the latest developments in light energy conversion. The following conversation provides insights into the scientific issues related to energy conversion. EL (ACS Energy Letters): How did you get interested in solar energy research so early in your career? Meyer: Early in my faculty career at UNC, in the 1970s, two of our early research interests were electron-transfer reactions and polypyridyl complexes of Ru(II) and Os(II). At the time, I had a very useful collaboration with Dave Whitten, now on the faculty at the University of New Mexico. Dave and his group had constructed a conventional flash photolysis apparatus, and it was a perfect moment for us to explore the excited-state electron transfer reactivity of the now famous triplet excited state “Ru(bpy)32+”. Initial experiments, with added methylviologen dication (MV2+) as the electron acceptor, worked like a charm providing clear evidence for excited-state quenching, with Ru(bpy)33+ and MV+ appearing after the flash with clear evidence for excited-state electron transfer. The initial finding was novel, at least back then, but there was something else. Based on the transiently stored redox energy in the products, Ru(bpy)33+ and MV+, sufficient excited-state energy was stored in the redox pair to split water into O2 and H2. For us, the rest was history. We carried on, often with no funding, over an extended period with an effort that led to our currently DOE funded Energy Frontier Research Center on Solar Fuels. EL: Some of your early work involved inorganic complexes as photosensitizers. Can you identif y a few major milestones? Meyer: As part of the larger effort on solar fuels, an early task was to elaborate and develop the background chemistry and photophysics of polypyridyl light absorbers of Ru(II) and Os(II). When I started my academic career at UNC, it was first target based on the earlier synthetic work of Dwyer and coworkers. In looking back, the early work on these complexes was remarkable for what we and others learned from synthesis to theory. In addition to electron transfer, it included early efforts on synthesis, with papers still cited today; theory, the latter developed by Ed Kober; and the use of multiple spectroscopies to understand and tune the excited states to control excited-state behavior. Application of the excited states in a variety of directions continues to evolve. EL: What are the current grand challenges in energy research? How does your Center contribute to these ef forts? Meyer: There are many challenges, especially at the hightech level. When I was the Associate Laboratory Director at Los © XXXX American Chemical Society
Received: September 28, 2016 Accepted: September 28, 2016 870
DOI: 10.1021/acsenergylett.6b00482 ACS Energy Lett. 2016, 1, 870−871
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economy based on the identification and exploitation of new and more versatile approaches to energy use and production. The nature of the problem will continue to evolve. The exploitation of hydrocarbons, with fracking and new hydrocarbon sources available in the U.S., will dominate our energy economy for now, but not other world markets. The impacts of hydrocarbons on the environment are clearly being felt, and their impact will continue to turn us more toward a “responsible” energy future, one of the goals of our current EFRC research effort. For those interested in a career in this area, focus on universities where research environments are in place with energy and energy issues playing a role. There are many problems waiting to be solved by you and your colleagues. The world’s energy future will depend on what you find.
Prashant V. Kamat, Editor-in-Chief, ACS Energy Letters
University of Notre Dame, Notre Dame, Indiana 46556 United States
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AUTHOR INFORMATION
Notes
The author declares no competing financial interest. Biography
Thomas J. Meyer is an Arey Professor of Chemistry at the University of North Carolina at Chapel Hill after rejoining the faculty in 2005. He is currently Director of the UNC Energy Frontier Research Center on Solar Fuels. In 2000 he was named Associate Director for Strategic Research at the Los Alamos National Laboratory in New Mexico. After receiving a BS from Ohio University in 1963, Meyer received a Ph.D. from Stanford in 1966 with Henry Taube as his research mentor. He joined the faculty of UNC in 1982. Meyer is a member of the National Academy of Sciences and the American Academy of Arts and Sciences and has won many prizes for chemical research. His research has been notable for pioneering, innovative discoveries in chemical reactivity and applications to important problems in chemistry and solar energy conversion. (Source: http://meyergroup.web.unc.edu/about-meyer/; photo courtesy of UNC University Photographer Jon Gardiner)
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EDITOR'S NOTE Views expressed in this Viewpoint are those of the author and not necessarily the views of the ACS.
871
DOI: 10.1021/acsenergylett.6b00482 ACS Energy Lett. 2016, 1, 870−871
