EPA
NEWS OF THE W EEK
ENVIRONMENT AGENCY SCIENCE REVIEWED REPORT: National Research Council advises EPA to improve coordination
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EPA’s science efforts include monitoring streams and their organisms in the western U.S.
HE ENVIRONMENTAL PROTECTION Agency
needs to bolster coordination among science efforts within the agency to strengthen its scientific capacity, the National Research Council concludes in a report issued last week. Scientific work at EPA has a strong foundation, the report finds. The agency, however, must change how it studies and then acts on persistent and emerging environmental challenges such as climate change and human exposure to an increasing number of chemicals in the environment. Members of Congress and others perceive EPA’s Office of Research & Development (ORD) as establishing the agency’s science agenda, says Jerald L. Schnoor, who chaired the committee that wrote the report. But only a quarter of the agency’s 6,000 scientists work at ORD, the report says. Many scientists work in regulatory of-
HOW HYDROGEN EVOLVES WATER SPLITTING: Study detects
and characterizes elusive reaction intermediate
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Y DESIGNING and using a tailor-made catalyst
to slowly mediate electrochemical combination of protons to produce hydrogen, researchers at California Institute of Technology have detected an elusive reaction intermediate and deduced key steps in the mechanism of the hydrogen evolution reaction (Proc. Natl. Acad. Sci. USA, DOI: 10.1073/pnas.1213442109). The investigation may offer new strategies for designing fast-acting, inexpensive catalysts that tap electrical energy to liberate hydrogen from water. Such electrocatalysts may be incorporated into future devices that convert solar energy to electrical energy, which in turn splits water into O2 and H2. H2 can be stored as a source of carbon-free chemical energy. Several synthetic transition-metal complexes, including ones based on cobalt, have been shown to be adept at facilitating the proton-combining step. Researchers have proposed a variety of mechaWWW.CEN-ONLIN E .ORG
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fices on water, air, waste, or chemical control; some work in the agency’s economic analysis unit; and others are at one of EPA’s 10 regional offices. With the wide dispersion of scientific activities, the report says, the agency needs more effective coordination and integration of its efforts to stay on the leading edge of science. It recommends that a senior official be given authority to oversee this work and ensure that the agency has the scientific and technical expertise it needs to support its research and regulatory actions. The report points out that only ORD plans for science, research, and budget needs. “Otherwise, There’s no real planning, either budgetary or strategic, across the entire agency,” says Schnoor, who is a University of Iowa environmental engineering professor and editor-in-chief of Environmental Science & Technology. EPA needs to change this situation, he says. The agency needs to prioritize its science needs, “especially in light of the declining budget,” Schnoor tells C&EN. “On the other hand, EPA officials shouldn’t be shy about articulating their need for resources.” In addition, the report says the agency needs to cultivate transdisciplinary efforts among its science staff. EPA also should add to its scientific and technical expertise, especially by hiring more behavioral, social, and decision scientists, the report recommends. EPA, which requested the report, had no comment on it by C&EN’s deadline.—CHERYL HOGUE
nisms that invoke transient cobalt species in attempts to sort out the molecular-scale events underpinning that normally rapid process. The fleeting nature of such intermediates makes it challenging to observe them directly. To probe the reaction mechanism, the Caltech team designed a catalyst, a Co-tris(diphenylphosphino) complex, that mediates H2 evolution slowly enough to allow the processes to be monitored. On the basis of NMR spectroscopy, the team, which includes Smaranda C. Marinescu, Jay R. Winkler, and Harry B. Gray, reports that the key intermediate is a previously undetected Co(III) hydride. According to Gray, the study shows that electron transfer converts the Co(III) hydride to a Co(II) hydride, which reacts in acid solution to acquire a proton and liberate H2. The work also shows that a competing process, in which two Co(III) hydride complexes react homolytically to split off a molecule of hydrogen, proceeds far more slowly than the Co(II) protonation step. “This study provides new insights into the mechanism of cobalt catalysts for hydrogen production,” says Sharon Hammes-Schiffer, a chemistry professor at the University of Illinois, Urbana-Champaign. She notes that the novel aspects of this study are the characterization of the transient Co complex and a kinetics analysis that reveals two competing pathways. “The mechanistic insights gained from this work are likely to assist in the design of more effective catalysts for hydrogen production,” she adds.—MITCH JACOBY
S E PTE M BE R 10, 20 12
