Polypyrrole–NiO hybrid nanocomposite films: highly selective, sensitive, and reproducible NO2 sensors

Abstract

Polypyrrole–nickel oxide (PPy–NiO) hybrid nanocomposite thin-film sensor was prepared by spin-coating method on glass substrate. The PPy–NiO hybrid nanocomposite thin film sensors were used to study room temperature gas-sensing properties for oxidizing (NO2, Cl2) as well as reducing (NO2, H2S, C2H5OH, NH3, and Cl2) gases. It was revealed that PPy–NiO (50 %) hybrid nanocomposite thin-film sensor could detect NO2 at low concentration (100 ppm) with very high selectivity (47 % compared with Cl2) and high sensitivity (47 %), with better stability (90 %) and reproducibility. The response and recovery times were changed significantly with NO2 concentration.