Ultrasensitive, Thin-film Sensors for the Trace Detection of Explosives

P. Ricci, O. Gregory
University of Rhode Island,
United States

Keywords: YSZ, Thermal Mass, TATP, Sensitivity, Selectivity

Summary:

There is a growing need for a continuous monitoring system that can detect explosives such as triacetone triperoxide (TATP) in the vapor phase at trace levels. TATP is an explosive commonly used by terrorists in improvised explosive devices both as the initiator and the energetic material itself. TATP is still going largely undetected in many densely-populated venues such as train stations and airports. No electronic trace detection system currently exists that is capable of continuously monitoring TATP, or its precursors, in the vapor phase. Recently, we developed a thermodynamic sensor that can detect TATP and 2,4 DNT at the ppb level. These ultrathin sensors show excellent selectivity and sensitivity through a unique sensing mechanism. This mechanism relies on specific oxidation-reduction reactions between the energetic molecules and metal oxide catalysts films on the surface of our microheaters. These sensors measure the heat effect associated with the redox reactions taking place on the metal oxide catalyst surface. Based on this mechanism, enhanced sensitivity and selectivity was achieved through implementation of ultrathin (