Flexible Composites from Water-Dispersible Components: Poly(vinyl alcohol), Janus Nanoparticles, and Polyaniline─Toward Mixed Ionic–Electronic Conductors

As the demand for multifunctional materials increases within the realm of electronics and photonics, composites that support both ionic and electronic charge transports are emerging as a promising platform for the future generation of electronic materials and devices. This study develops and characterizes a green composite material, utilizing a nonconductive poly(vinyl alcohol) (PVA) matrix integrated with glycerol (Gly) for enhanced ionic conductivity and mechanical flexibility, amphiphilic Janus nanoparticles (JNPs), and in situ synthesized polyaniline (PANi). The incorporation of JNPs, modified to possess either insulating or semiconducting properties through a semiconducting PANi layer on one of the Janus lobes, and the synthesis of PANi within the composite matrix are key to achieving mixed ionic–electronic conductivity, crucial for advanced dielectric functionalities. Employing broadband dielectric spectroscopy, this study assesses the composite's electrical and dielectric properties, focusing on the interplay and polarization mechanisms induced by each component. Results reveal that glycerol's contribution to ionic conductivity through a hydrogen bond network is significant, while JNPs/PANi add distinct electronic transport pathways, indicating a complex yet effective charge transport system within the composite. The utilization of water as a solvent emphasizes the material's suitability for environmentally sustainable applications in electronics and photonics, presenting its potential in next-generation device architectures.