Sensing Performance of Blended PCL-PEI Polymers-Based Nanocomposites: Material Characterization and Application to Gas Detection

Hybrid nanocomposites (HNs) have distinguishing characteristics due to electron transition, making them interesting for required applications. The study focused on the impact of graphene oxide (GO) independently, then functionally with silicon dioxide (SiO₂) to reinforce blended polycaprolactone and polyethyleneimine. Nanocomposites revealed homogeneous and rough surfaces in the polymer matrix using field-emission scanning electron microscopy. Remarkably, the AC conductivity of the GO-SiO₂ sample revealed better results than the GO sample, whereas the samples that included functional nanomaterials exhibited the best results of 3.4 × 10⁻³ S cm⁻¹. At RT, Nitrogen Dioxide (NO₂) and Ammonia (NH₃) gas were detected by HNs samples, presenting a high sensitivity of 54.7% for NH₃ and having approximately the same recovery time of about 25 s for both gases, whereas the best response time was 10.8 s for NO₂ gas. At 100 °C, the NH sample exhibited better sensitivity and recovery time of NO₂ than NH₃. At 150 °C, the results were similar for both gases, but were variable at 200 °C. Functional GO with SiO₂ nanomaterials achieved better results than using GO as a single nanomaterial, making these compounds an excellent candidate for gas sensing with excellent sensitivity and suggesting new nanocomposites for advanced applications.