Theoretical and experimental study of sensing triacetone triperoxide (TATP) explosive through nanostructured TiO2 substrate

• Development of sensor platform for detection of peroxide explosive molecule like TATP.
• Metal functionalized TiO2 nanostructure shows promising results.
• Computational study is applied to select the suitable metal to be functionalized in detection device; Co2+ is computed to be the suitable one.
• Understanding the fundamental mechanisms in interaction of metal ions with TATP.

The present study focuses on understanding of the principle of interaction of explosive molecule triacetonetriperoxide (TATP) with metal sensitized TiO2 nanotube composite material through theoretical modeling. This effort has also been extended in developing a laboratory scale sensor set up to detect TATP based on comprehensive computational modeling outcome and subsequent experimentation. Sensing mechanism depends on the nature of metal, where the TATP interaction with metal functionalized TiO2 prompts a change in conductivity of the sensor platform. Therefore, a metal with higher affinity towards TATP would enhance the conductance, thereby promoting the efficiency of the sensor platform. DFT methodology has been used to identify metal with high affinity to TATP. It was found that Co2+ metal ion shows significantly higher affinity towards TATP, selected from an array of metal ions with different valency, from monovalent to tetravalent. The preliminary experimental data also suggests that Co2+ ion detects TATP by inducing a change in conductivity of the sensor substrate.