Investigating Mass and Charge Transport in Organic Electrochemical Transistors for Use as Explosives Sensors.

Organic electrochemical transistors (OECTs) have attracted interest as they can be applied to a number of sensing and electronic challenges, and they provide a means to probe mass and charge transport present in electrolyte-gated systems. These phenomena can be altered by augmenting device architecture with either chemically selective or functionalized components. In particular, we supplement OECTs, which utilize poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) channels, with a molecularly imprinted polymer (MIP) barrier. These MIPs combine size exclusion and functional chemistry during their synthesis. These features render them highly selective to specific molecules and. The resulting architecture is then applied towards the detection of explosive species (i.e., energetic materials). The collective family of energetic materials contains a variety of species and includes covalently bound organics as well as ionically charged species. Aside from enabling selective detection, introducing such a barrier forces neutral molecules and electrically driven ionic species to competitively permeate through the barrier. Investigating these phenomena will help illuminate key molecule-pore binding principles and design strategies for new sensing arenas.