Performance of dmmp sensing using silver-modified zeolite/polypyrrole composite materials

We present the hydrothermal synthesis of Linde Type L zeolite and the preparation of its composite through chemical polymerization for gas-sensing applications. The main objective of this work is to improve the sensing performance of the zeolite-based nano-composite. The resulting materials were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Fourier-transform infrared spectroscopy (FTIR). XRD patterns confirmed the high crystallinity of the zeolite and Ag-modified zeolite, while the broad peaks observed for polypyrrole indicated its amorphous nature. SEM images revealed that incorporating polypyrrole into the zeolite matrix altered the morphology, shifting from a rectangular structure to more spherical features. This modification reduced particle size and increased the surface area, contributing to enhanced sensing capability. The gas-sensing performance of the composite toward DMMP was evaluated using copper electrodes coated with the material through a drop-casting approach. Key sensing parameters—including response and recovery times, sensitivity, and selectivity—were systematically examined. Overall, the nanocomposite exhibited excellent sensing performance across various concentrations of DMMP vapors.