Synthesis and processing of π-conjugated derivatives in aqueous media: Introducing sustainability in printed electronics

Sustainability in the synthesis and processing of organic semiconductors is becoming increasingly important as the field progresses from fundamental research to technological deployment. Volatile organic solvents dominate the environmental footprint of both laboratory-scale and industrial production, significantly increasing hazardous waste generation. Substituting these solvents with water dramatically reduces environmental impact while enabling new reactivity modes and formulation strategies. Recent developments demonstrate that water is not only a benign solvent for synthetic chemistry but also a robust medium for preparing stable, printable, and device-compatible inks of conjugated materials. This review highlights advances in aqueous-phase synthesis as well as modern aqueous processing routes such as surfactant-stabilized dispersions, hydrotropic systems, and self-emulsifying conjugated polymers. These approaches illustrate how water can serve as a unifying platform for high-performance and environmentally responsible printed electronics.