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Bioinspired Chemistry for Energy: A Workshop Summary to the Chemical Sciences Roundtable
2
Government, Industry, and Academic Perspectives on Bioinspired Chemistry for Energy
During three different sessions of the workshop, government, industry, and academic representatives presented perspectives on bioinspired chemistry for energy. Representing the federal government were Eric Rohlfing of the U.S. Department of Energy’s (DOE’s) Office of Basic Energy Sciences; Michael Clarke of the National Science Foundation’s (NSF’s) Chemistry Division; Judy Raper of NSF’s Division of Chemical, Bioengineering, Environmental and Transport Systems; and Peter C. Preusch of the National Institutes of Health’s (NIH’s) Pharmacology, Physiology, and Biological Chemistry Division. The industry perspective was provided by Henry Bryndza of DuPont, Brent Erickson of the Biotechnology Industry Organization, and Magdalena Ramirez of British Petroleum (BP). Daniel Nocera from the Massachusetts Institute of Technology discussed the issue from an academic point of view.
GOVERNMENT PERSPECTIVE
Eric Rohlfing, DOE, discussed the bioinspired chemistry for energy work being done in the agency’s Office of Basic Energy Sciences (BES). The office funds basic research that will lead to revolutionary discoveries to address energy issues. He categorized the work being done into three broad areas, although he did not go into detail about the third since it is not in the division he manages. The overall theme of these areas is to learn from nature but also to figure out how to accomplish tasks more quickly.
Learning how to convert sunlight into chemical fuels like nature does, only better.
Detailed studies of the molecular mechanism of natural photosynthesis to create artificial systems that mimic some of the remarkable traits of natural ones (i.e., self-assembly, self-regulation, and self-repair) while improving efficiency.
Work encompasses light harvesting, exciton transfer, charge separation, redox chemistry and uses all the tools of the modern physical sciences in conjunction with molecular biology and biochemistry.
Learning catalysis tricks from nature.
Apply lessons learned from natural enzymes to the design of organometallic complexes and inorganic and hybrid solids that catalyze pathways with unique activity and selectivity.
Characterize the structure and dynamics of active sites in enzymes and the correlated motions of secondary and tertiary structures. Measure half-lifetimes of individual steps of electron- and ion-transport during catalytic cycles. Synthesize ligands for metal centers and functionalize inorganic pores to attain enzyme-like activity and selectivity with inorganic-like robustness.
Learning from nature about how to make novel materials.
Emphasis on the merger of biological and inorganic systems at the nanoscale.
Rohlfing presented an organizational chart of the Chemical Sciences, Geosciences, and Biosciences Division, which he manages. He pointed out the four programs in the division that are working on bioinspired chemistry for energy: Solar Photochemistry, Photosynthetic Systems, Physical Biosciences, and Catalysis Science. The goal of these programs is to define and understand the structure, biochemical composition, and physical principals of natural photosynthetic energy conversion.
A major research goal of BES is to figure out how photosynthesis works and then design artificial or biohybrid
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Bioinspired Chemistry for Energy: A Workshop Summary to the Chemical Sciences Roundtable
systems that directly produce solar fuels better than plants do to avoid having to use plants. Rohlfing presented three examples of research sponsored by BES that demonstrate how chemistry relates to dynamics and change.
First, the Fenna-Matthews-Olson, or FMO, complex is a bacteria-chlorophyll complex that acts as a photosynthetic system (Figure 2.1). It is a conduction device for transporting the electrical energy when harvesting light. Researchers are trying to determine how energy is transferred along the set of chlorophylls. Is it by energy hopping or is there some more complex physical process? Coherent spectroscopy based on a femtosecond photon-echo technique in the visible region of the spectrum was applied to the FMO complex to determine whether there is quantum coherence (quantum beats) in the system. Quantum coherence is important because it helps avoid kinetic traps, explained Rohlfing.
The second example of research being funded by DOE involves a model system, metalloporphyrin, which looks at excited-state evolution using time-resolved X-rays. This research sets the groundwork for future research that will be conducted on much shorter time scales than the femtosecond domain.
The third research project presented by Rohlfing looked at the intrinsic motions of proteins as they influence catalysis and enzymes. Characterizing the intrinsic motions of enzymes is necessary to fully understand how they work as catalysts. As powerful as structure-function relationships are, the motion of these proteins is intimately connected with their catalytic activity and cannot be viewed as static structures. This realization, asserted Rohl fing, could revolutionize and accelerate approaches to biocatalyst design or directed evolution, and could alter understanding of the relations between protein structure and catalytic function.
The next speaker was Michael Clarke of NSF’s Chemistry Division. He explained that the NSF funds a broad range of science and that the agency is concerned about making energy sustainable and solving the carbon dioxide problem.
Next he discussed the method that NSF uses to fund the scientific research. It has a program that was originally called the Chemical Bonding Centers but is now morphing into Centers for Chemical Innovation, which makes a number of relatively small awards, around $500,000, to fund groups of
FIGURE 2.1 Model of the photosynthetic apparatus (Fenna-Matthews-Olson complex) in Chlorobium tepidum.
SOURCE: Donald A. Bryant, The Pennsylvania State University, and Dr. Niels-Ulrik Frigaard, University of Copenhagen.
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Bioinspired Chemistry for Energy: A Workshop Summary to the Chemical Sciences Roundtable
scientists who collaborate in addressing a major chemistry problem. For example, Harry Gray, Kitt Cummins, Nate Louis, Dan Nocera, and others are working on a project involving the direct conversion of sunlight into fuel. They are in the initial stages of the program and have received about $500,000 so far. After several years, the research teams can apply for funding of several million dollars per year. Other similar research projects being funded by NSF (detailed below) focus on carbon dioxide, photochemical physics of charge separation, and finding a way to organize supermolecular structures in various ways using weak bonds, hydrogen bonds, and covalent bonds.
Carbon dioxide
Marcetta Darensbourg, Texas A&M University: Looking at carbon-carbon coupling reactions as mediated by transition metals. The nickel sites serve as the catalyst.
Geoffrey Coates, Cornell University: Using a solid-state catalyst to incorporate carbon dioxide into polycarbonates.
Donald Darensbourg, Texas A&M University: Pioneered the use of metal catalysts for converting the nontoxic, inexpensive carbon dioxide and three-membered cyclic ethers (epoxides) to thermoplastics, which are environmentally friendly and productively use greenhouse gas emissions. He is also working on developing effective nontoxic metal catalysts for producing a biodegradable polycarbonate from either trimethylene carbonate or trimethylene oxide and carbon dioxide.
Janie Louie, University of Utah: Using platinum and nickel catalysts that allow carbon dioxide to be used as a starting material for organic synthesis.
Photochemical physics of charge separation
Dmitry Matyushov, Arizona State University: Using a ferroelectric medium to facilitate charge transfer since the main cause of inefficiency of current artificial photosynthesis is fast charge recombination following photoinduced charge transfer. This research has succeeded in reducing the recombination rate.
Francis D’Souza, Wichita State University: This research is focused on using assembled nanosystems to separate charges and facilitate transfer, and involves an interdisciplinary team of researchers (Figure 2.2).
Finding a way to organize supermolecular structures in various ways using weak bonds, hydrogen bonds, and covalent bonds
Dan Reger, University of South Carolina: Using water to organize organic molecules into a nanostructure.
Clarke said that finding a way to organize supermolecular structures needs to be done in order to affect charge transfers. Forming fuels are synthesized by using all of the types of bonding that chemists have available to them to bring together the various components in organized structures, noted Clarke.
Judy Raper of NSF’s Division of Chemical, Bioengineering, Environmental and Transport Systems explained how NSF takes a broad view of bioinspired chemistry. Some of the main areas that NSF focuses on are:
Bioinspired nanocatalysis for energy production that involves using starch (corn) or cellulose (wood) to produce renewable fuels and chemicals.
Bioinspired hydrogen production.
Production of liquid biofuels (both ethanol and alkanes).
Microbial fuel cells.
Raper explained that NSF programs support the following bioinspired chemistry for energy research under the National Biofuels Action Plan: metabolic engineering, plant genome research, catalysis and biocatalysis, biochemical
FIGURE 2.2 Supramolecular nanostructures for light driven energy and electron transfer. This research is focused on rational design and study of self-assembled porphyrin, fullerene, and carbon nanotube bearing supramolecular complexes and nanostructures.
SOURCE: Presented by Michael Clarke, National Science Foundation; used with permission from Francis D’Souza, Wichita State University.
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Bioinspired Chemistry for Energy: A Workshop Summary to the Chemical Sciences Roundtable
and biomass engineering, biotechnology, energy for sustainability, environmental sustainability, and organic and macromolecular chemistry. She highlighted some of the currently funded NSF projects.
In the area of bioinspired catalysis, Raper mentioned the work of a few researchers. Dennis Miller and James Jackson at Michigan State are exploring taking starch or cellulose, extracting the carbohydrate, and fermenting it to organic acid and glycerols. Robert Davis at the University of Virginia is looking at gold nanoparticles as catalysts for the conversion of glycerol to glyceric acid.
Raper also highlighted work in the area of bioinspired hydrogen production and microbial fuel cells. David Dixon at the University of Alabama is studying photocatalytic production of hydrogen. Bruce Logan of Pennsylvania State University is looking at hydrogen production by fermentation of waste water (as well microbial fuel cells for energy production; Figure 2.3). Dianne Ahmann at the Colorado School of Mines is using Fe-hydrogenase to produce commercial algal hydrogen. Lars Angenent of Washington University Nonfermentable products in wastewater are being used to produce electricity in microbial fuel cells.
NSF also supports production of liquid biofuels. James Dumesic at the University of Wisconsin is looking at green gasoline, which involves using inorganic catalysts to make alkanes, jet fuels, and hydrogen. Dumesic is breaking up cellulose to make aqueous phase reforming through syngas for alkane products, hexane, and through hydroxymethyfurfural to make jet fuels or polymers. Ramon Gonzales at Rice University is exploring anaerobic fermentation of glycerol in E.coli for biofuels production.
FIGURE 2.3 Power Generation with Microbial Fuel Cells.
SOURCE: Presentation of Judy Raper, National Science Foundation; used with permission from Bruce Logan, Pennsylvania State University.
Peter C. Preusch of the Pharmacology, Physiology, and Biological Chemistry Division of the National Institute of General Medical Sciences at the NIH discussed the agency’s mission and how bioinspired chemistry for energy fits into it. The mission of NIH is to pursue fundamental knowledge about the nature and behavior of living systems and the application of that knowledge to extend healthy life and reduce the burdens of illness and disability. That mission, asserted Preusch, has allowed interesting dual-use science to be supported that is relevant to both basic energy research and human health. NIH has a large budget but nothing earmarked for research in this area. The National Institute of General Medical Sciences is one of the largest supporters of chemical sciences research in the nation, said Preusch.
The bioinspired chemistry research that has been supported by NIH falls into two categories: (1) chemical models of biological processes for the purpose of better understanding those biological processes and (2) using chemistry that is related to biology or using biological catalysts to accomplish chemical processes at a scale that is industrially significant.
Preusch provided examples of investigator-initiated grant-based projects funded by NIH that address fundamental physical processes and reactions of elements that are important in both global energy cycles and human health. Note that NIH has not solicited proposals in this area, but has supported a considerable amount of research that reflects investigator-initiated ideas in the field.
Energy transfer: How light energy is captured, transmitted from an initial absorbing molecule through a series of intermediate molecules to a site at which that energy is captured in the form of electron-proton separation across a membrane.
Electron transfer: Basic to the function of the respi ratory chains of mitochondria and bacterial pathogens.
Oxygen activation: Work on mimics of cytohrome P450 to understand how they function and use catalysts in order to activate molecules for oxygen insertion and to activate oxygen.
Oxygen reduction: Models have been created for cytochrome oxidase, which have provided insights into the oxygen activation and reduction mechanism.
Hydrogen peroxide: Model studies on catalases, peroxidases, and superoxide dismutases have provided insights into biological protection against oxidative damage.
Hydrogen reduction: Model studies of hydrogenase provide insights relevant to the pathogenic organism Helicobacter pylori and its ability to survive in the gastric mucosa.
Nitrogen oxide production and reduction: Relevant to the production and disposal of nitrogen oxides as signaling molecules and biological responses to environmental nitrogen oxides.
Nitrogen reduction: Nitrogenase has been a model system for studying general principles involving electron
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Bioinspired Chemistry for Energy: A Workshop Summary to the Chemical Sciences Roundtable
transfer, energy coupling, fundamental structures of metal complexes, and the chemical control of their assembly.
At the end of his talk, Preusch described the grant application and award process for regular research grants, conference grants, and academic research enhancement awards.
INDUSTRY PERSPECTIVE
Henry Bryndza of DuPont began his presentation by emphasizing how expansive the subject area of this Bioinspired Chemistry for Energy workshop can be, stating, “When I think about ‘bioinspired,’ it means everything from biomimetics to superior process technology for bioprocesses, through integrated science approach, to even the production of chemicals and materials that are enabled by an emerging infrastructure in renewably available feedstocks. Similarly, when you’re talking about ‘energy,’ it’s not only energy production in terms of conventional sources that are in widespread use today but also so-called alternative or renewable energies.” He also said that recycling and use minimization should be considered in the overall energy picture.
Bryndza believes that a tipping point has been reached in the drive for alternative energy sources and that they offer significant potential for future growth. The success or failure of alternative energy sources, claimed Bryndza, has major implications for the United States as well as for the planet in terms of political climate, environmental performance, and economic health. He believes it is unlikely that there will be one global solution; rather, he thinks there are going to be local minima that are dictated, in part, by availability and cost of technology and its capital intensity. The availability and cost of feedstocks vary by region, and different governments have different subsidies, regulations, incentives, and policies that will also drive the local minima for fast adoption.
Bryndza explained how DuPont is a science company that is heavily dedicated to the energy market and sustainable growth. He talked about the company’s sustainability policies that were established in 1989 and updated in 2006. By 2010, Bryndza estimated 25 percent of revenues from DuPont’s businesses are expected to be derived from operations using raw materials that are not depleted, and 10 percent of the company’s energy needs will be derived from renewable sources.
Bryndza then touched on the selection criteria that DuPont uses to decide which projects to undertake. Projects must be consistent with the corporate vision and sustainability principles, unique, multigenerational, consistent with DuPont competences, have a valid route to market, and DuPont’s stake needs to be large enough to justify the effort.
DuPont is already heavily invested in products, services, and research in support of global energy markets as diverse as petrochemicals, fuel cells, photovoltaics, and biofuels. The company supplies products to the sugar- and corn-based ethanol industries. Offerings under development from biomass feedstocks include improved biomass to energy, crop protection chemicals, and cellulosic ethanol and butanol technologies coming from biorefineries.
Biomass includes a range of materials from simple plant oils and sugars that can be converted into liquid transportation fuels to cellulose, hemicellulose, and lignocellulose which are successively much harder to address. Bryndza explained that there are many potential conversion processes that deliver energy in different ways, ranging from distributed power or stationary power to liquid transportation fuels. DuPont is working on a number of different conversion processes and trying to identify the most efficient ones. The cellulosic ethanol program is a consortium effort involving other companies, government laboratories, and academia. The project is looking at a variety of chemical and biological technologies to convert biomass into useful products ranging from fuels to chemicals and materials. DuPont thinks that the variation in biomass feedstocks will require an integration of sciences and multiple technologies.
Bryndza believes that integration is important to finding the best solution to the world’s energy crisis. If scientists approach energy problems from either a biological perspective or a chemical perspective, asserted Bryndza, alternative energy technologies will not work economically. He said, “We really need partnerships…. We are partnering in virtually all of these areas for a couple of reasons. One is that we can’t do it all ourselves. The second is that, in some cases, partners bring technology or access to markets that we don’t have.”
Brent Erickson of the Biotechnology Industry Organization (BIO) said his organization is the world’s largest trade association, with over 1,000 member companies in 33 countries. It represents the gamut of biotechnology from health care to food and agriculture biotech to industrial and environmental biotech. According to Erickson, pharmaceutical and agriculture areas are already well developed, so the next wave is fuels, chemicals and manufacturing, biopolymers, chiral intermediates, and products for farm and fine chemicals. BIO advocates on Capitol Hill are currently trying to gain support from policy makers for biorefinery development.
Erickson provided several reasons why industrial biotech is important for innovation and commercialization:
Because process innovation is slowing, the chemical industry must identify new places to find innovation.
Energy prices and availability of petroleum-based feedstocks are problematic.
The global marketplace is becoming increasingly competitive.
Industrial biotech is advancing rapidly, providing new tools for innovation, cost reduction, and improving environmental performance.
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Bioinspired Chemistry for Energy: A Workshop Summary to the Chemical Sciences Roundtable
Industrial biotech represents a broad range of applications, including biobased products, bioenergy, biobased polymers, and national defense. The Department of Defense, for example, has a program to build mobile biorefineries that recycle kitchen waste.
Erickson’s vision for the future includes creating a biobased economy in which the basic building blocks for industry and raw materials for energy are derived from renewable plant sources and are processed using industrial biotechnology. According to Erickson, technologies should be developed that go beyond a simple starch-to-ethanol platform that exists now.
Erickson believes that industrial biotechnology is attractive to business because it can decrease production costs and increase profits, increase the sustainability profile, allow for broader use of renewable agricultural feedstocks instead of using petroleum, and provide precision catalysis. However, he thinks industrial biotechnology can also be disruptive as it converges with other scientific disciplines because of its shorter research and development cycles. Erickson then discussed the importance of partnership among companies, which is detailed in Chapter 5.
So how will the biobased economy actually happen? Erickson believes that radically new business models will appear that challenge traditional companies, but unique opportunities for the fast movers will be created. Companies that are early adopters of industrial biotech will gain a competitive advantage in the marketplace, said Erickson.
What is the market potential? Industrial biotech is already 5 percent of global chemical production, and Erickson believes it will continue to accelerate rapidly. McKinsey and Company estimates that by 2010 industrial biotech could be worth $280 billion.
In conclusion, Erickson stated that, “industrial biotech and biological chemistry are really at the right place at the right time with the right tools to make a big difference in our energy security, our economy, and our environment.”
Magdalena Ramirez of BP focused on crude oil refining using biocatalysis and biotechnologies. She addressed achievements of biorefining and potential interaction of conventional refining and biorefining. There have been large investments made in crude oil biorefining over the last 20 years, but that has only reached the pilot-plant scale. Crude oil refining is complex, said Ramirez, as hydro-cracking and hydrotreatment occur at very high temperatures and pressures. The products of crude oil refining include petroleum gases, naphtha, kerosene, gas oil (diesel oil), lubricating oil, fuel oil, and residue which are made up of a variety of molecules rather than a single molecule.
According to Ramirez, biocatalytic processes could be useful in crude oil refining because:
they moderate conditions such as pressure and temperature;
the chemistry is oxygen-based compared to hydrogen in hydrotreatment;
the handling is facilitated by the conditions used;
selectivity in biocatalysis involves a specific compound, while catalytic hydrotreatment involves a family of compounds;
their application addresses improvements in product quality;
they may minimize pollution and waste;
they simplify the refining process by reducing separation and disposal stages; and
they offer economic benefits.
Ramirez then highlighted some achievements in biorefining. A wide range of biocatalysts have been discovered from research at the cellular and subcellular level and have evolved through cloning and engineering of the microbial catalyst. Catalytic properties have been improved by broadening the selectivity of the biocatalyst. A more thermally stable catalyst has been patented and an attempt has been made to integrate those processes into refinery operations. Ramirez said that catalytic activity has particularly been improved for enzymes involved in desulfurization. A large effort in enzyme isolation and characterization has been made. Although some of the enzymes are known to contain metal clusters or metal sites, Ramirez noted that very little is known about their chemical nature and their catalytic role in the enzymatic action. She claims that scientists need to understand these issues in order to contribute to technology development.
Other biological processes have also been considered for improving refining. Ramirez sees that regulations on sulfur are becoming tougher and the supply of heavy oil is growing, leading to higher sulfur content in the feedstocks. Therefore, said Ramirez, producing the required cleaner products involves overcoming more difficult challenges. In conventional refining the hydrogen needs increase the operational costs, as a result of finding new chemistries for removing sulfur. Not much is known about the active site in the biological catalysts or the molecular mechanisms. Ramirez explained that the metabolic pathway of desulfurization is well established. The pathway links the intermediate metabolites of the reaction, but it is not known how one molecule is converted into another. Performance relationships that are well known in chemistry or in ordinary heterogeneous or homogeneous catalysis are not valid in the biocatalytic mechanisms.
Does it make sense to mimic the structural catalyst or to mimic how they work? Ramirez thinks that scientists need to understand the function rather than the structure of biocatalysts, and that scientists should investigate how biocatalysts work rather than what they are. It is important, said Ramirez, to address the selectivity issues and improve the performance of a biocatalyst when mimicking ordinary chemistry. She feels that stability should be addressed
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Bioinspired Chemistry for Energy: A Workshop Summary to the Chemical Sciences Roundtable
because biocatalysts are not stable at the conditions that refineries normally operate and that catalysis should be as efficient as possible.
Ramirez expects that biorefining will bring new insights into refining, new chemistry, and new processes that are more energy efficient and emphasize of product quality. In the end collaboration will lead to greener solutions for refining.
ACADEMIC PERSPECTIVE
Daniel Nocera of the Massachusetts Institute of Technology began his presentation by discussing a paper he wrote for the Proceedings of the National Academy of Sciences in 20061 in which he introduced a roadmap for chemistry’s role in the energy problem. The rest of presentation focused on breaking the nearly linear dependence of energy use and carbon (i.e., replacing coal, gas, and oil). Nocera stated that the world is on an oil curve in terms of depending on carbon for primary-energy use. If coal is going to be used, posed Nocera, more efficient processes for mining, burning, and sequestering carbon should be developed. Population, GDP per capita, and energy intensity determine how much energy will be needed.
Nocera explained that the chemical equation for his research is oil = water + light. High-energy bonds, such as carbon-carbon, hydrogen-hydrogen, and oxygen-oxygen, are rearranged to produce a fuel. When they are burned, bonds are rearranged to produce energy. Nocera believes that the best crops to use for biomass conversion in terms of light energy storage are switchgrass, miscanthus, and cyanobacteria. Corn is the crop that is usually mentioned, said Nocera, because of the corn industry’s lobbying effort and because conversion of starch to ethanol is well understood. Corn is an energy-intensive crop, requiring a large amount of energy to generate high-energy polymers in sugar and starch versus cellulose and lignin. Switchgrass and miscanthus have hardly any sugar or starch in them; they are made up of cellulose and lignin. Therefore, new microbes or thermochemical catalysts for lignin and cellulose conversion need to be discovered, said Nocera.
Nocera is concerned about the amount of carbon dioxide in the atmosphere, and he showed a public education video that he helped produce. He believes the carbon dioxide problem can be solved with water and light, which involves bond rearrangement. Therefore, said Nocera, the only types of energy that will work, from a renewable and sustainable perspective, are biomass, photochemical, and photovoltaic. He sees a problem with biomass in that it is also a food source, so biomass could be limited to a minor role in the energy future.
Nocera then discussed how photosynthesis demonstrates a bioinspired design. He suggested setting up a wireless current that is driven by the sun. A cathode, which produces hydrogen, would be placed on one end and an anode on the other. Reduction would take place and the anode would drive water oxidation. The process ends up separating catalysis from capture and conversion.
Nocera listed the main factors that will change for enacting solar energy:
Cheap and efficient PVs;
Replace noble metal catalysts (for fuel and solar cells) with inexpensive metals;
New chemistry for water splitting.
He noted the need to manage electrons and protons, assemble water, and transfer atoms to make solar energy efficient with cheap catalysts. His team has developed several new techniques, such as proton-coupled electron transfer (which he noted as a human health issue). This technique is related to energy because it is how energy is stored in the biology realm. Nocera provided some examples of research being done in this area. One project involves inventing multielectron chemistry with mixed valency in which metals can be changed by two electrons using ligands (Figure 2.4).
The main conclusions from Nocera’s presentation were:
The need for energy is so enormous that conventional, long-discussed sources will not be enough.
Solar + water has the capacity to meet future energy needs.
But large expanses of fundamental molecular science need to be discovered. There are many intriguing problems to study.
FIGURE 2.4 Three projects demonstrating multielectron chemistry with mixed valency.
SOURCE: Presented by Daniel Nocera.
1
Lewis, N. S. and D. G. Nocera. 2006. PNAS 103: 15729-15735.
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Renewable energy research is not an engineering problem. It has to be tackled as a basic science problem. Catalysis and many new modes of reactivity await discovery.
Chemistry is the central science of energy because it involves light capture and conversion with materials and storage in bonds.
The problem is too important to let our scientific egos get in the way. There needs to be an honest broker (i.e., objective group of scientists) who can recommend an honest representation of the strategic investment for energy.
Following Nocera’s presentation, John Turner of the National Renewable Energy Laboratory said that the processes that Nocera discussed are missing something in the theory that would explain how to make the inorganic materials mimic what has been done with ruthenium and platinum. Turner thinks there are too many combinations and a better directed approach is needed. Turner also suggested that they get theorists involved in the process to help understand synthesis and characterization. Nocera agreed with Turner’s comment.
John Sheats of Rider University pointed out that along with the increasing need for energy, a population of nine billion people will need to be fed. He posed the question, “Can we use biomass for fuel and feed the world when we’re not currently feeding the world?” Nocera responded with a simple “Yes,” and mentioned that the food dilemma is why the problem of biomass conversion needs to move on to lignin and cellulose. Nocera stressed using other energy sources besides biomass. He explained that if the majority of the world’s energy needs were addressed by using biomass, then there would indeed be a problem.