p-Hexafluoroisopropanol phenyl functionalized graphene for QCM based detection of dimethyl methylphosphonate, a simulant of the nerve agent sarin

The detection of DMMP (dimethyl methylphosphonate, a simulant of nerve agent sarin) was performed by using p-hexafluoroisopropanol phenyl (HFIPP) functionalized graphene (GR) via hydrogen bond interactions. For this, the HFIPP moiety was covalently functionalized on the surface of GR by a diazo reaction. The HFIPP-GR film-modified QCM electrodes were fabricated and their sensing characteristics towards DMMP were investigated. The proposed sensor showed good response towards sensing DMMP vapor at room temperature. In order to see the effect of HFIPP derivatives on DMMP vapor sensing, a comparative study was also conducted with unfunctionalized graphene. The sensitivity and detection limit of the HFIPP-GR sensor against DMMP vapors were 12.24 Hz ppm(−1) and 150 ppb respectively. The HFIPP-GR coated sensors showed good selectivity towards sensing DMMP vapors when compared with common organic vapors.