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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: A chemical sensor fabricated from gold nanoparticles and poly(2-hydroxyethyl methacrylate) (PHEMA) is presented and its chemi-resistive, chemi-capacitive and chemi-impedance performance is investigated. Detection of humidity and ethanol in the range of 2000–20,000ppm has been made possible in all the above cases. The sensor was fabricated following a two step process utilizing ink-jet printing to deliver both nanoparticles and PHEMA on oxidized silicon substrates: first a layer of nanoparticles has been delivered on top of gold interdigitated electrodes followed by the successive deposition of PHEMA polymer. By controlling several key design parameters such as nanoparticle size, number of ink-jet printed gold nanoparticles and electrode spacing, the fabrication of chemical sensors with different sensing response and linearity is 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]

Abstract: The fabrication of a chemical sensor based on the technique of gold nanoparticle ink-jet printing and the subsequent functionalization of the nanoparticle film by Polyhydroxyethylmethacrylate (PHEMA) polymer is presented while its chemiresistive, chemi-capacitive and chemi-impedance response are investigated. By controlling the Gold nanoparticle density and selecting different interdigitated electrode distances and nanoparticle sizes, chemical sensors of different linearity and sensitivity can be obtained. [ABSTRACT FROM AUTHOR]