Associate Professor James Blakemore named January 2025 Sutton Family Research Impact Award recipient
The Department of Chemistry congratulates Associate Professor James Blakemore on receiving the January 2025 Sutton Family Research Impact Award!
The Sutton Award is a monthly competition among chemistry faculty. Every month, the Chemistry Department Chair and Associate Chairs review the peer-reviewed papers published by chemistry faculty from the three previous months to select a winner. The recipient receives a $500 cash prize and is featured on the departmental website.
For a full list of winners, visit our Sutton Family Research Impact Award webpage.
PCET-Driven Reactivity of Neptunyl(VI) Yields Oxo-Bridged Np(V) and Np(IV) Species
Emily R. Mikeska,1,2 Richard E. Wilson,*,2 and James D. Blakemore*,1
1 Department of Chemistry, University of Kansas
2 Chemical Sciences and Engineering Division, Argonne National Laboratory
Neptunium (Np) is an artificially prepared transuranium element in the actinide series, and one that is found in significant quantities in the used fuel from nuclear power plants. For this reason, even though the chemistry of Np may not be immediately familiar to all chemists, understanding and controlling it are critically important in nuclear fuel recycling and waste management. Motivated by research needs in this arena, Associate Professor James Blakemore and his research group (shown in Figure 1) have established a collaboration with Dr. Richard Wilson of Argonne National Laboratory to study the redox properties and reactivity of complexes of heavy elements like Np. Dr. Wilson is an expert in the chemistry of transuranium elements, and Dr. Blakemore’s group focuses on controlling the reactivity of metal complexes of heavy elements with tailored ligands, electrochemical methods, and related strategies.
Figure 1. The Blakemore Group pictured on May 3, 2024. Dr. Blakemore is standing in the back row, second from right. Dr. Emily Mikeska, seated third from the right, and Davis Curry, seated first on the left in the front row, directly contributed to portions of the work described in this article.
In the recently published article selected for the January 2025 Sutton Award, which was also recently featured on the Front Cover of Chemistry – A European Journal, a type of reactivity known as proton-coupled electron transfer (PCET) was identified and investigated for a series of Np complexes. The PCET reactivity in the studied system appears to drive the formation of multimetallic species by coupling together the movement of both electrons (redox) and protons (acid/base chemistry). PCET has been studied heavily in transition metal chemistry, and has proven exceedingly successful in assisting chemists in understanding and controlling reactivity in various settings. Consequently, the observation that PCET or PCET-like reactivity can be used to understand the reactivity of actinide elements like Np could represent a new opportunity to control chemistry in the actinide series. In the findings reported in the featured paper, former KU graduate student and Blakemore Group member Dr. Emily Mikeska studied how Np redox chemistry was coupled to acid/base reactions that led to the formation of two different oxo-bridged multimetallic complexes of Np. The two different complexes were isolated as crystals and were investigated by X-ray diffraction analysis as well as spectroscopy (see Figure 2).
Figure 2. Molecular structures of the multimetallic, oxo-bridged neptunium complexes, denoted [Np3O4] and [Np2O3], from single-crystal X-ray diffraction analysis described by Mikeska, Wilson, and Blakemore. Outer-sphere solvent molecules, all hydrogen atoms, and the minor orientations of organic ligand backbone disorder are omitted for clarity.
Dr. Blakemore’s group and Dr. Wilson are continuing their work together, and anticipate that the type of chemistry reported in this paper could be useful for addressing the properties and reactivity of other actinide-containing systems. Along this line, graduate student Davis Curry is currently studying at Argonne with Dr. Wilson as a SCSGR Program appointee. Current research is showing that the type of reactivity elucidated in this paper is indeed possible in other transuranium systems, and results from this newer work are currently being written up for publication. Overall, the path forward for the collaborative research appears quite promising, and more exciting results are anticipated to emerge from the collaboration in the months ahead.