Faculty Research
Alphabetical · By research area

Research in our group lies within the domains of synthetic inorganic and polymer chemistry with particular focus given to addressing important challenges in energy, catalysis, and sensing technologies. A key component of our program involves examining the cooperative interaction between reactive inorganic sites (based on either main group or transition metal elements) with the goal of uncovering new reaction pathways. Researchers in the Rivard group will be exposed to a number of advanced inorganic and polymer synthesis and characterization methods, including quantum mechanical calculations.

Functional Polymers: Hydrogen Storage and the "Hydrogen Economy"

Polymers are a ubiquitous and essential part of modern living and brand-name polymers such as Nylon, Teflon, Latex and Kevlar are now entrenched in our vocabulary. However as impressive as these materials are, their utility is largely based on their physical properties rather than their ability to undergo chemical processes. Functional polymers combine the useful physical properties of traditional polymers with the added advantage of pre-designed chemical reactivity.

One of the projects in this area involves the construction of polymers that are able to store/release large quantities of hydrogen for fuel cell technologies. The use of hydrogen as a fuel alternative to gasoline, often termed the "hydrogen economy", is of considerable promise in light of the ongoing depletion of traditional hydrocarbon fuel sources and the negative impact the burning of fossil fuels has on the environment. As outlined in the schematic below, we will prepare a number of robust polymers which have reactive sources of H₂ appended to the main polymer chain. By heating these polymers in a controlled fashion, we hope to generate hydrogen in a clean process (i.e. no volatile byproducts). Added advantages of a polymer-based hydrogen storage system are high hydrogen storage densities and improved safety in comparison to pre-existing hydrogen storage materials. In addition, we will explore efficient methods to chemically re-charge the remaining polymer after the release of hydrogen, thus completing the H₂ release/uptake cycle.

Reactive Rings: Lewis Acidic Macrocycles (LAMs) and Multi-metallic Frameworks

Research in this area will start with a simple question: is more the merrier? Specifically, does the incorporation of multiple electron-deficient (Lewis acidic) borane groups within in a single molecule lead to increased acidity and reactivity when compared to a solitary borane, R₃B. These highly Lewis Acidic Macrocycles (LAMs) will be examined in the context of various sensing applications due to their potential ability to cooperatively bind various analytes. Also, the use of these species as potential activators for olefin polymerization will be explored.

We are also interested in ligands that place two low-coordinate (and low-oxidation state) transition metals in close proximity in order to encourage the cooperative activation of small molecules (as shown below). One goal of this work is the synthesis of important commodity molecules and polymers from simple feedstock molecules such as the environmentally noxious CO₂ using bimetallic activation.

Selected Publications

"Isomeric Forms of Heavier Main Group Hydrides: Experimental and Theoretical Studies of the [Sn(Ar)H]₂ (Ar = Terphenyl) System", E. Rivard, R.H. Herber, S. Nagase, P.P. Power et al., Journal of the American Chemical Society, 2007, 129, 16197-16208.

"Multiple Bonding in Heavier Element Compounds Stabilized by Bulky Terphenyl Ligands", E. Rivard and P.P. Power, Inorganic Chemistry, 2007, 46, 10047-10064.

"A Donor-Stabilization Strategy for the Preparation of Compounds Featuring P=B and As=B Double Bonds", E. Rivard, W.A. Merrill, J.C. Fettinger, P.P. Power, Chemical Communications, 2006, 3800-3802.

"Structural Snapshots of a Flexible Cu₂P₂ Core that Accommodates the Oxidation States Cu^ICu^I, Cu^1.5Cu^1.5 and Cu^IICu^II", N.P. Mankad, E. Rivard, S.B. Harkins, J.C. Peters, Journal of the American Chemical Society, 2005, 127, 16032-16033.

"Reversible Skeletal Transmetallation of Inorganic Rings: Isolation of Aluminatophosphazenes, a Zwitterionic Phosphazene, and a Donor-Stabilized Alumazine-Phosphazene Hybrid Cation", E. Rivard, P.J. Ragogna, A.R. McWilliams, A.J. Lough, I. Manners, Inorganic Chemistry, 2005, 44, 6789-6798.

"Donor-Stabilized Cations and Imine Transfer from N-Silylphosphoranimines", E. Rivard, K. Huynh, A.J. Lough, I. Manners, Journal of the American Chemical Society, 2004, 126, 2286-2287.