Effect of Stability of Two-Dimensional (2D) Aminoethyl Methacrylate Perovskite Using Lead-Based Materials for Ammonia Gas Sensor Application

Changes in physical properties of (H2C=C(CH3)CO2CH2CH2NH3)2PbI2Cl2 and (H2C=C(CH3)CO2CH2CH2NH3)2Pb(NO3)2Cl2 (2D) perovskite materials from iodide-based (I-AMP) and nitrate-based (N-AMP) leads were investigated at different durations (days) for various storage conditions. UV-Vis spectra of both samples showed an absorption band of around λmax 420 nm due to the transition of n to π* of ethylene (C=C) and amine (NH2). XRD perovskite peaks could be observed at approximately 25.35° (I-AMP) and 23.1° (N-AMP). However, a major shift in I-AMP and dramatic changes in the crystallite size, FHWM and crystallinity percentage highlighted the instability of the iodide-based material. In contrast, N-AMP showed superior stability with 96.76% crystallinity even at D20 under the S condition. Both materials were exposed to ammonia (NH3) gas, and a new XRD peak of ammonium lead iodide (NH4PbI3) with a red-shifted perovskite peak (101) was observed for the case of I-AMP. Based on the FWHM, crystallite size, crystallinity and lattice strain analysis, it can be concluded N-AMP's stability was maintained even after a few days of exposure to the said gases. These novel nitrate-based lead perovskite materials exhibited great potential for stable perovskite 2D materials and recorded less toxicity compared to famous lead iodide (PbI2) material.