K. Nigorikawa et al., A SELECTIVE GAS SENSOR USING A POLYPYRROLE THIN-FILM AS A SENSITIVE MATRIX ON A PIEZOELECTRIC CRYSTAL, Journal of electroanalytical chemistry [1992], 396(1-2), 1995, pp. 563-567
A novel gas sensor is fabricated on the basis of simultaneous measurem
ents of resistance changes (Delta R) and mass changes (Delta M) of a c
onducting polypyrrole (PP) film assembled on a piezoelectric crystal.
Molecular species such as acetone, methanol and ethanol can be recogni
zed by the (Delta R/R(0))/(Delta M/M(0)) values, where R(0) and M(0) a
re the initial resistance and weight of the PP film respectively. In c
ontrast, the quantitative analysis of the vapour molecules can be achi
eved by measuring the Delta R/R(0) or Delta M/M(0) values. For a serie
s of primary alcohols the homologues can also be recognized by the sim
ultaneous measurement of Delta R and Delta M. Moreover, it is shown th
at this sensor is usable to clarify the interactions between the PP fi
lm and the vapour molecules.