Activities are focused on investigations of catalysis-related, waste-free and low-carbon technologies combining the individual strengths to form a strong team with excellent coverage of relevant topics. The program is unified with a focus on transformations of “small molecules” (H2, O2, H2O, CO2), all of which impact green technologies. This interdisciplinary knowledge is also required for training the next generation of scientists.
● RESEARCH HIGHLIGHTS AND ACCOMPLISHMENTS
Molecular catalysts have the advantage of being highly variable in terms of design, and solution-phase catalysis is important because it enables us to directly observe the details of the mechanism. Fuel cell development can be taken in an entirely new direction by the introduction of molecular catalysts, capable of working in homogeneous solutions. We have applied the novel catalytic action of our NiRu catalyst to both sides of a fully functioning fuel cell. This is only the first step in a radical new approach to fuel-cell catalysis. In addition, we will develop a high-efficiency, novel cathode catalyst that is inspired by O2-tolerant [NiFe]H2ases, instead of a Pt-based heterogeneous catalyst.
Inspirations for our work on FCs are the enzymes that support life in air-breathing organisms. Progress has been made on biomimetic Fe-Cu catalysts that reduce dioxygen to water at low overpotentials. The work has also led to the detection of O2-bound intermediates in homogeneous systems. These developments underpin a powerful new concept of membrane-less FCs that contain catalysts selective for both cathode and anode reactions.
Overlapping with work on ORR, another theme deals with oxidative processes, exploiting our skills in materials science and organic synthesis. New heterogeneous catalysts have been developed consisting of alloys of iron-group metals, Fe-Co-Ni and applied to the oxidation of the commodity chemical ethylene glycol. Correspondingly, we have developed homogeneous catalysts composed of Fe-salan-naphthoxide complexes, which catalyze the corresponding aerobic conversions of secondary alcohols. The work has been extended to broadened substrate range, exploiting the role of hydrogen-bonding between substrate and catalyst, a theme of continuing interest across the entire team. Advances have also been made in catalysts for water oxidation and proton reduction. These two reactions comprise the ultimate devices that will produce solar fuels.
● FUTURE DIRECTIONS
Emphasis on small molecules and fuel cells and solar energy will continue. The team will expand cross-training of students, leading to cross-fertilization of projects.