Conductive Polymers: Green Synthesis and Applications in Environmental Remediation

Conductive polymers are emerging as strategic materials for environmental technologies, combining redox activity, tunable conductivity, chemical stability and processability. Recent literature highlights polyaniline, polypyrrole and polythiophene-based systems as promising adsorbents and photocatalytic platforms for the removal of dyes, heavy metals, volatile organic compounds and emerging contaminants from water and air matrices. Among them, polyaniline (PANI) is particularly attractive owing to its acid/base doping–dedoping chemistry, affinity toward organic and inorganic pollutants, and ability to act either as an active sorbent or as a photosensitizer in semiconductor-based composites. However, conventional PANI synthesis still relies on hazardous oxidants and may generate toxic by-products and large amounts of inorganic waste. In this contribution, we present our recent advances toward sustainable conductive polymers prepared through green oxidative polymerization routes using molecular oxygen, hydrogen peroxide and light-driven processes under mild conditions. Catalyst-assisted strategies based on Au, Cu, Fe₃O₄, CoFe₂O₄ and TiO₂ enable the synthesis of conductive polymers and multifunctional nanocomposites with controlled morphology, porosity, magnetic response and surface chemistry. The resulting materials were successfully applied to environmental remediation, including VOC adsorption, hydrocarbon removal from water, dye sorption/photodegradation and Cr(VI) abatement. Particularly, PANI/TiO₂ systems combine adsorption and photocatalysis, while floating solar-light-active composites offer easy recovery and reuse, addressing one of the major limitations of powdered photocatalysts. Overall, this work demonstrates how green chemistry and conductive polymer design can converge into scalable, recyclable and high-performance materials for next-generation environmental remediation.