Permanently porous conjugated polymers for the detection of low-volatility explosives
Low-volatility explosives pose a threat to public safety and military safety. These compounds, such as pentaerythritol tetranitrate (PETN), were implicated in recent failed terrorist acts (such as by the infamous “shoe bomber” in 2002). With appropriate tools, authorities can identify these chemical signatures from these explosives and take preventative action. A highly successful strategy based on fluorescence quenching of conjugated polymers has achieved commercial and military adoption for detecting trinitrotoluene (TNT); however, lower-volatility explosives, such as PETN and cyclotrimethylenetrinitramine (RDX), still require physical contact with a pre-concentrator (swabs seen at airports) or well-trained dogs. Thus, it is highly desirable to improve the sensitivity of conjugated materials such that they detect vapors of low-volatility explosives. My work focuses on pursuing major sensitivity gains by investigating emerging polymer architectures with high surface area and long-range order. Our strategy is to increase the surface area and dimensionality of conjugated pathways within the sensing material. Examples of sensing TNT vapors and other high explosives using nanoporous conjugated polymers will be presented.