Neodymium Oxide Embedded Polypyrrole Matrix for Humidity Sensing Applications

In-situ chemical polymerization was employed to synthesize a polypyrrole matrix embedded with rare earth oxide, resulting in the formation of polypyrrole-neodymium oxide (PPy/Nd<inf>2</inf>O<inf>3</inf>) composites with varying weight percentages of Nd<inf>2</inf>O<inf>3</inf> (10, 30, and 50). The crystalline properties of these composites were elucidated through XRD spectra. The SEM images of the PPy/Nd<inf>2</inf>O<inf>3</inf> − 50% composite indicated a uniform distribution of Nd<inf>2</inf>O<inf>3</inf> within the PPy matrix, characterized by smaller grain sizes. Furthermore, TEM analyses corroborated the crystalline structure of the composite, confirming the incorporation of Nd<inf>2</inf>O<inf>3</inf> within the PPy matrix. FTIR spectra demonstrated the interfacial interactions between PPy and Nd<inf>2</inf>O<inf>3</inf>, as well as the composite’s formation. The composites’ capacity to detect humidity was assessed across a relative humidity spectrum of 10% to 97%. Notably, the PPy/Nd2O3–50% composite exhibited a rapid response time of 30 seconds and a recovery duration of 34 seconds, alongside commendable linearity (0.9991), sensitivity, and detection limits.