'Major Discovery' From Caltech & MIT Primed To Unleash Solar Revolution

http://www.nsf.gov/awardsearch/showAward.do?AwardNumber=0829114

ABSTRACT

CBET-0829114 Haile More energy from sunlight strikes the earth in one hour than all of the energy consumed on the planet in one year. Thus, the challenge modern society faces is not one of identifying a sustainable energy source, but rather one of capitalizing on the vast solar resource base. To truly transform our energy production technologies, we need to go beyond efficient capture of solar energy for immediate electricity generation and turn to the problem of convenient storage of the energy from this intermittent source for on-demand utilization. To address this challenge of solar energy at night, we propose an elegant strategy that relies on the oxygen uptake and release capacity of selected metal oxides. Specifically, a metal oxide is cycled between, for example, MO2 and MO2-, using thermal energy as the input and the changes in oxidation state utilized to produce a chemical fuel, as shown schematically for hydrogen production in the panel. The thermal energy ideally derives from solar-thermal concentration, but may also be derived from nuclear power plants. In this work, we specifically focus on ceria-based oxides, which have already demonstrated promise for this application, while pursuing exploratory studies using oxides with wide non-stoichiometry ranges and rapid oxygen transport kinetics. By careful selection of the reaction substrate and/or judicious use of catalysts, we anticipate production not only of hydrogen fuel, as shown in the panel, but also carbon containing fuels (syngas, methane, methanol) when carbon dioxide is used as an additional input reactant. Beyond the bulk nature of the material, we will explore the role of architecture in optimizing fuel productivity. We will fabricate monolithic reaction substrates based on inverse opal structures, which combine the features of low tortuosity (low resistance to gas phase mass transport), short solid state diffusion paths and sufficiently high surface and are more robust against coarsening and performance degradation than particle based reaction substrates. The experimental plan thus encompasses a broad range of thermodynamic and kinetic studies to elucidate reaction pathways, which, in turn, are essential for system optimization. Beyond the fundamental scientific questions concerning the thermochemical production of fuels that these studies will answer, the proposed work addresses the key technological challenge of solar energy storage. As envisioned, the fuel production process is simple, utilizes earth-abundant elements, and permits production of a variety of reduced chemical fuels (H2, CH4, CH3OH, etc.). The breadth of tools to be utilized combined with the high level of public interest in energy technologies renders this an ideal program for training future materials scientists. Furthermore, the continued commitment of the PI to public outreach (through, for example, the PI's participation in the California Science Center exhibits on fuel cells for transportation and for sustainable energy) will ensure that these results are disseminated to society as a whole. For this program in particular, the PI is committed to hosting two summer high school students who will come to Caltech via the Institute for Educational Advancement.


http://mr.caltech.edu/media/Press_Releases/PR13172.html

Caltech Scientists Awarded $20 Million to "Power the Planet"

PASADENA, Calif.--In the dreams of Harry Gray, Beckman Professor of Chemistry at the California Institute of Technology, the future energy needs of the world are met with solar-fuel power plants. Now, a $20 million award from the Chemical Bonding Center (CBC), a National Science Foundation (NSF) Division of Chemistry program, will help bring this dream one step closer to reality.

In 2005, NSF granted three Phase I CBC awards. Gray formed a group of Caltech and MIT scientists who spent the $1.5 million and three years of Phase I conducting initial research and establishing public outreach plans for their idea.

Of the three Phase I projects, Caltech's is the only one to advance to Phase II, a $20 million, five-year extension. "We have added outstanding investigators from many other institutions to our Caltech-MIT team in order to ramp up our efforts in Phase II of the 21st century grand challenge to make solar fuels using materials made from Earth-abundant elements," says Gray.

In Phase I, the Caltech-MIT alliance, called "Powering the Planet," proposed to develop nanoscale materials to make fuel from sunlight and water. They designed a nanorod-catalyst water splitter that incorporates a membrane to separate the oxygen- and hydrogen-making parts of the system.

Nathan Lewis, Caltech's Argyros Professor and professor of chemistry, and chemist Bruce Brunschwig, a Member of Caltech's Beckman Institute (BI) and Director of the Materials Resource Center for the BI, headed a group of students and postdocs who began working on a silicon nanorod-studded plastic sheet to harvest sunlight. The hydrogen-making catalyst team was headed by Gray, Jay Winkler (a Caltech faculty associate in chemistry), and Jonas Peters (a former Caltech chemistry professor now at MIT). Research with the goal of finding efficient catalysts for the oxidation of water to oxygen was led by MIT scientists Dan Nocera, a former graduate student of Gray's, and Christopher Cummins.

With a conceptual design in place, and with promising results in all three investigation areas, the alliance expanded--18 senior researchers at 12 institutions signed on to compete for Phase II of the CBC award and participate in testing and refining the nanoscale water-splitting device.

Luis Echegoyen, Director of the NSF Division of Chemistry, says, "The Division of Chemistry is pleased and excited to establish this new CBC devoted to elucidating some basic science aspects of solar energy research. This center and its excellent team of researchers will enable NSF to partner with the scientific community to explore fundamental aspects of solar-driven splitting of water into hydrogen and oxygen."

The CBC Program is designed to support the formation of centers that can address long-term, high-risk, and high-impact basic chemical research problems. The centers are expected to be responsive to rapidly emerging opportunities and make full use of cyberinfrastructure to enhance collaborations.

"We are excited about our prospects, as we are lucky to have a very talented and dedicated group of students and postdocs who are ready and able to tackle the fundamental chemistry problems that must be solved before it will be feasible to produce clean solar fuels on a large scale," Gray adds. The Phase II award may be extended for an additional five years.

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For more information on the award, visit http://www.nsf.gov/awardsearch/showAward.do?AwardNumber=0802907.

Contact: Kathy Svitil (626) 395-8022 ksvitil@caltech.edu

http://web.mit.edu/newsoffice/2008/nsf-solar-0804.html

Team led by MIT, Caltech wins $20 million grant
Funds to support push for solar-fuel power plants

August 4, 2008

A team led by MIT and Caltech scientists has been awarded $20 million to help pursue the dream of meeting the world's energy needs with solar-fuel power plants.

The grant from the Chemical Bonding Center (CBC), a National Science Foundation (NSF) Division of Chemistry program, will fund the "Powering the Planet" alliance for five years.

In 2005, NSF granted a Phase I CBC award to the group of Caltech and MIT scientists, who spent the $1.5 million and three years of Phase I conducting initial research and establishing public outreach plans for their idea.

In Phase I, the team proposed to develop nanoscale materials to make fuel from sunlight and water. They designed a nanorod-catalyst water splitter that incorporates a membrane to separate the oxygen- and hydrogen-making parts of the system.

MIT members of the team include Daniel Nocera, the Henry Dreyfus Professor of Energy and professor of chemistry, and chemistry professors Christopher Cummins and Jonas Peters.

The work has yielded promising results, and the alliance has expanded to 18 senior researchers at 12 institutions, who have signed on to participate in testing and refining the nanoscale water-splitting device.

(Note: This text was adapted from a news release originally issued by Caltech.)

http://www.poweronline.com/article.mvc/MIT-researchers-transform-so...


'Major Discovery' From MIT Primed To Unleash Solar Revolution

August 4, 2008

Cambridge, MA - In a revolutionary leap that could transform solar power from a marginal, boutique alternative into a mainstream energy source, MIT researchers have overcome a major barrier to large-scale solar power: storing energy for use when the sun doesn't shine.

Until now, solar power has been a daytime-only energy source, because storing extra solar energy for later use is prohibitively expensive and grossly inefficient. With today's announcement, MIT researchers have hit upon a simple, inexpensive, highly efficient process for storing solar energy.

Requiring nothing but abundant, non-toxic natural materials, this discovery could unlock the most potent, carbon-free energy source of all: the sun. "This is the nirvana of what we've been talking about for years," said MIT's Daniel Nocera, the Henry Dreyfus Professor of Energy at MIT and senior author of a paper describing the work in the July 31 issue of Science. "Solar power has always been a limited, far-off solution. Now we can seriously think about solar power as unlimited and soon."

Inspired by the photosynthesis performed by plants, Nocera and Matthew Kanan, a postdoctoral fellow in Nocera's lab, have developed an unprecedented process that will allow the sun's energy to be used to split water into hydrogen and oxygen gases. Later, the oxygen and hydrogen may be recombined inside a fuel cell, creating carbon-free electricity to power your house or your electric car, day or night.

The key component in Nocera and Kanan's new process is a new catalyst that produces oxygen gas from water; another catalyst produces valuable hydrogen gas. The new catalyst consists of cobalt metal, phosphate and an electrode, placed in water. When electricity — whether from a photovoltaic cell, a wind turbine or any other source — runs through the electrode, the cobalt and phosphate form a thin film on the electrode, and oxygen gas is produced.

Combined with another catalyst, such as platinum, that can produce hydrogen gas from water, the system can duplicate the water splitting reaction that occurs during photosynthesis.

The new catalyst works at room temperature, in neutral pH water, and it's easy to set up, Nocera said. "That's why I know this is going to work. It's so easy to implement," he said.

'Giant Leap' For Clean Energy

Sunlight has the greatest potential of any power source to solve the world's energy problems, said Nocera. In one hour, enough sunlight strikes the Earth to provide the entire planet's energy needs for one year.

James Barber, a leader in the study of photosynthesis who was not involved in this research, called the discovery by Nocera and Kanan a "giant leap" toward generating clean, carbon-free energy on a massive scale.

"This is a major discovery with enormous implications for the future prosperity of humankind," said Barber, the Ernst Chain Professor of Biochemistry at Imperial College London. "The importance of their discovery cannot be overstated since it opens up the door for developing new technologies for energy production thus reducing our dependence for fossil fuels and addressing the global climate change problem."

'Just The Beginning'

Currently available electrolyzers, which split water with electricity and are often used industrially, are not suited for artificial photosynthesis because they are very expensive and require a highly basic (non-benign) environment that has little to do with the conditions under which photosynthesis operates.

More engineering work needs to be done to integrate the new scientific discovery into existing photovoltaic systems, but Nocera said he is confident that such systems will become a reality.

"This is just the beginning," said Nocera, principal investigator for the Solar Revolution Project funded by the Chesonis Family Foundation and co-Director of the Eni-MIT Solar Frontiers Center. "The scientific community is really going to run with this."

Nocera hopes that within 10 years, homeowners will be able to power their homes in daylight through photovoltaic cells, while using excess solar energy to produce hydrogen and oxygen to power their own household fuel cell. Electricity-by-wire from a central source could be a thing of the past.

The project is part of the MIT Energy Initiative, a program designed to help transform the global energy system to meet the needs of the future and to help build a bridge to that future by improving today's energy systems. MITEI Director Ernest Moniz, Cecil and Ida Green Professor of Physics and Engineering Systems, noted that "this discovery in the Nocera lab demonstrates that moving up the transformation of our energy supply system to one based on renewables will depend heavily on frontier basic science."

The success of the Nocera lab shows the impact of a mixture of funding sources – governments, philanthropy, and industry. This project was funded by the National Science Foundation and by the Chesonis Family Foundation, which gave MIT $10 million this spring to launch the Solar Revolution Project, with a goal to make the large scale deployment of solar energy within 10 years.

SOURCE: MIT