Advanced polymer-based humidity sensor for aerospace applications implementing ZnO-G: theoretical and experimental study.

Monitoring the surroundings relies on aerospace sensors to provide immediate information on the purity of the air, temperature, humidity, and atmospheric pressure. Aerospace and space mission environmental monitoring essentials sophisticated humidity sensors for aerospace. Humidity sensor efficiency, reliability of data, and future expansion are the challenges. Selection of polymer-based nanocomposites yields innovative humidity sensor hybrid nanocomposites with sensitive, stable, robust, low cost, simple to handle, and real-time features. The research field lacks knowledge regarding the effects of these metal oxides (MOs) on essential polymer composition and humidity sensitivity, despite their ability to increase active sides and surface area for humidity detection. A theoretical investigation was conducted to examine the impact of different MOs on the sensitivity, stability, and electrical characteristics of a Polyvinyl Alcohol (PVA) matrix. The interaction among various MOs and the PVA matrix produces the formation of new active chemical groups, thereby improving the sensitivity and reactivity of PVA. The observed reactivity is associated with the elevated surface energy exhibited by PVA, with the optimal modification observed being the incorporation of Zinc oxide (ZnO) nanofiller. Fabricated sensors with PVA-ZnO based have potential for advancement by integrating recent additional ingredients particularly graphene (G), which may create innovative composite PVA-ZnO-G to immediately enhance the surface characteristics of reactivity, thereby improving humidity detection sensitivity. The PVA-ZnO-G hybrid nanocomposite was synthesized, and its surface and intermolecular characteristics were studied, along with reactivity, hardness, softness, sensitivity and selectivity, were analyzed for humidity sensing. When evaluating the PVA-ZnO-5H2O complex against the PVA-ZnO-G -5H2O complex, it is evident that the latter exhibits superior electronic characteristics. Notably, it possesses a larger dipole moment of 21.0848 Debye, a reduced band gap of 0.503 eV, and a significantly more favorable adsorption energy of -0.7592 eV. The corresponding increase in the equilibrium constant (log K = 12.8380) further indicates that PVA-ZnO-G is thermodynamically practical and exhibit enhanced stability and sensitivity. In particular, the mechanical and thermal properties were enhanced, and the electrical environment was fundamentally altered to facilitate increased H2O interaction because of the hybridization of ZnO and the incorporation of G into the matrix.