Polyacrylamide gel synthesis of CuO/CuFe2O4 nanoparticles for H2S gas sensing

Abstract In the present work, CuO/CuFe₂O₄ nanoparticles were synthesized via a polyacrylamide gel. The produced nanocomposites were utilized as a gas sensor for the detection of H₂S gas. The nanoparticles were characterized via XRD, FTIR, SEM and TEM techniques. XRD results revealed that the as-prepared product was amorphous and CuO and CuFe₂O₄ phases were formed after calcination at 800°C. Microstructural studies showed that the nanoparticles have a particle size distribution ranging from 60 to 120 nm. Most of the particles had a spherical morphology. The polyacrylamide network acted as a template for the formation of the nanoparticles. The H₂S gas sensing characteristics of the products were studied at different concentrations and operating temperatures. In addition, the effect of humidity on the gas-sensing response was investigated. The prepared CuO/CuFe₂O₄ sensors can respond up to 25 when exposed to 10 ppm H₂S which is higher than the pure CuO or CuFe₂O₄ sensors. The sensors reached a detection limit of 0.1 ppm and demonstrated clear sensitivity and quick response and recovery behavior toward H₂S gas. The CuO/CuFe₂O₄ heterogeneous nanostructures also showed proper H₂S gas response and selectivity in response to interfering gases like NH₃, NO₂, HCHO and CO. The gas sensing mechanism of the composites was also discussed.