Engineered PANI/Carbon Dot Hybrids Materials for Advanced Chemiresistive Gas Sensors

Chemiresistive gas sensors based on conducting polymers have attracted significant attention due to their low cost, room‑temperature operation, and ease of processing. However, challenges related to selectivity and long‑term stability still limit their widespread application and practical deployment. In this context, hybrid materials combining conducting polymers with functional nanostructures represent a promising strategy to improve sensing performance through synergistic physicochemical effects.
This work reports the preparation and physico‑chemical characterization of hybrid polyaniline/carbon dots (PANI/CDs) composites. Nitrogen‑doped carbon dots were synthesized via microwave‑assisted carbonization of citric acid and urea, enabling precise control over particle size and surface functionalities. These features are crucial for tailoring interfacial interactions and creating potential adsorption sites relevant to gas sensing applications. The CDs were subsequently blended with polyaniline using a solvent‑free, mechanical mixing approach, allowing the formation of homogeneous conductive composites through a simple, scalable, and environmentally friendly process, without the need for complex chemical treatments.
The resulting PANI/CDs materials were investigated by spectroscopic and morphological techniques to assess their structural, compositional, and interfacial characteristics. Particular attention was devoted to evaluating the dispersion of CDs within the polymer matrix and the resulting material homogeneity. Overall, the combination of controlled nanostructure synthesis and straightforward composite preparation highlights the potential of these materials as a versatile platform for developing low‑cost chemiresistive sensors for environmental and indoor air‑quality monitoring.