Facile Anhydrous Proton Transport On Hydroxyl Functionalized Graphene

Proton transport is a critical important property of proton exchange membrane (PEM) fuel cells. We propose a nano-structured material capable of fast water-free proton transport. These materials can be constructed from functionalized surfaces (e.g. graphene, SWNT, Si(001), MOFs, etc) with different functional groups (e.g. -OH, -COOH, -SO3H, -NH, etc.) that form hydrogen bonded networks. In this work, we predict that hydroxyl functionalized graphene will conduct protons in the complete absence of water due to a self-assembled hydrogen bond network of OH groups on the surface.  Activation energy of hydroxyl functionalized graphene is similar to that of Nafion, a standard polyelectrolyte proton exchange membrane. The single-file proton diffusion and proton mobility on the surface of both 1-D and 2-D hydrogen bonded graphane membranes will be discussed.

 

Acknowledgement

We gratefully acknowledge support from DTRA under Contract No. HDTRA1-09-1-0008 and from NSF TeraGrid (XSEDE) resources under allocation numbers [TG-DMR100097], [TG-SEE090006], and [TG-DMR110091]. We thank K. D. Jordan , M. E. Tuckerman and J. T. Yates, Jr. for helpful discussions. We thank the Center for Simulation and Modeling at the University of Pittsburgh for providing computational support.