Selective detection of SO2 at room temperature based on organoplatinum functionalized single-walled carbon nanotube field effect transistors

We report a field effect transistor (FET) based on a network of single-walled carbon nanotubes (SWCNTs) that for the first time can selectively detect a single gaseous molecule in air by chemically functionalizing the SWCNTs with a selective molecular receptor. As a target model we used SO2. The molecular synthetic receptor is a square-planar NCN-pincer platinum (II) complex (NCN is the N,C,N′-terdentate-coordinating monoanionic [C6H3(CH2NMe2)3-2,6]− ligand) to which SO2 selectively binds. Because of the strong electronwithdrawing character of SO2, it withdraws negative charge from the synthetic receptor thus affecting the electronic properties of the functionalized SWCNTs. The minimum concentration detected is 0.05% SO2 in air at room temperature. Interferences like CH4 and CO2 need to be present in a higher concentration than SO2 to give a significant response.