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Abstract: Platinum nanoparticles without any prior chemical modification and poly(2-hydroxyethyl methacrylate) (PHEMA) have been employed as the transducing and gas sensitive layer respectively for this flexible chemical sensing application. Using a modified magnetron sputtering technique, gas phase platinum nanoparticles have been deposited on top of flexible polyimide substrates. The surface density of such nanoparticle films can be controlled via the overall deposition time, producing devices of varying conductivity. A layer of PHEMA polymer (500–700nm thick) has been ink-jet printed on top of the nanoparticle film finalizing the sensor's fabrication. By exposing the sensor in ethanol or humidity vapors a change in the film's resistance or capacitance is observed facilitating the detection of such gases. The performance of these sensors has been connected with the nanoparticle film resistance. [Copyright &y& Elsevier]

Abstract: Chemical gas sensors have been fabricated from platinum and poly(2-hydroxyethylmethacrylate) (PHEMA) polymer. Sputtered platinum nanoparticles have been deposited on flat silicon substrates and a second layer of PHEMA polymer has been deposited on top using ink-jet printing. Density of the platinum nanoparticles and resistance of the device, which can both be tuned by controlling the deposition time, directly affect the response of the sensors as measured in the presence of ethanol and humidity. Chemi-resistive and chemi-capacitive sensors capable of detecting low gas concentrations (1000ppm of humidity and 500ppm of ethanol) have been made possible. [Copyright &y& Elsevier]

Abstract: A technique for the fabrication of chemiresistive sensors using ink-jet printing is reported. Gold nanoparticles stabilised in water were ink-jet printed on gold interdigitated electrodes patterned on an oxidized silicon wafer. As a first step the influence of substrate functionalization, electrode spacing, and nanoparticle density were investigated by electrical measurements and microscopy imaging. Finally a second layer of PHEMA polymer was printed on top of the gold nanoparticle films. The device was exposed to vapours of humidity and ethanol and the obtained results are presented. [ABSTRACT FROM AUTHOR]