Discrimination of Methanol from Ethanol in Gasoline Using a Membrane-type Surface Stress Sensor Coated with Copper(I) Complex
Michihiro Nishikawa, Tomohiro Murata, Shinsuke Ishihara, Kota Shiba, Lok Kumar Shrestha, Genki Yoshikawa, Kosuke Minami, Katsuhiko Ariga
Abstract
Abstract We successfully fabricated a novel sensing platform, a Membrane-type Surface stress Sensor (MSS) coated with copper(I) complex bearing phen and BINAP ligands, [Cu(phen)((±)-BINAP)]PF6 (1, phen = 1,10-phenanthroline, BINAP = 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl), for specific molecular sensing. Based on the transduction of mechanical stresses derived from sorption-induced deformation of Cu(I) complex, the detection performance of various volatile organic compounds (VOCs) has been investigated. The fabricated sensor devices showed selective responses to methanol over a wide range of VOCs. In addition, distinct MSS signals upon exposure to methanol were observed for mixing samples of methanol in n-hexane and gasoline with clear discrimination of ethanol mixtures. In fact, gasoline vapor with 1% methanol exhibited much higher MSS responses than 20% ethanol containing gasoline samples. Methanol contamination in gasoline and related petroleum samples is a world-wide common problem in the automobile and fuel sectors where detection of methanol contaminants with portable devices by easy procedures is required. The current research results will contribute to fulfilling these social demands.