Patent ID: 9598282
Date: 2017-03-21
CPC Classifications: B82Y,G01N,Y10S

Claim:
1. A chemical sensor comprising: a plurality of fibers whose electrical impedance varies upon exposure to a chemical species; a substrate supporting and electrically isolating the fibers; a set of printed electrodes disposed on at least one of the substrate and the plurality of fibers and connected to the plurality of fibers at spatially separated points to permit the electrical impedance of the plurality of fibers to be measured; and a polymer layer disposed in contact with the plurality of fibers to transport the chemical species from air outside the polymer layer through the polymer layer to provide a higher concentration of the chemical species at the fibers than in the air, wherein the fibers comprise conductive fibers, the conductive fibers comprise a non-conducting medium and a conducting additive medium dispersed in the non-conducting medium, and the conducting additive medium has a density which permits electrical conduction by percolation of charge carriers through regions of the conducting medium in the conductive fibers.