High-Performance Freshwater-Hydroelectricity Co-Generation by Porous Carbon through Waste Polyester-Derived MOF-Assisted Carbonization

• • The porous carbon derived from waste polyester via MOF-assisted carbonization achieves a high specific surface area of 904 m² g⁻¹, enabling efficient ion transport and photothermal conversion, which is critical for high-rate water evaporation and electricity generation. • • The bifunctional evaporator delivers an open-circuit voltage of 250 mV and a short-circuit current of 14 μA under 1 sun, demonstrating a practical pathway for simultaneous freshwater and electricity production from solar energy. • • The evaporation rate reaches 2.34 kg m⁻² h⁻¹ with a reduced water evaporation enthalpy of 1.7 kJ g⁻¹, indicating that the material's hierarchical pore structure and oxygen groups weaken hydrogen bonding, thereby lowering energy input for desalination. • • Mechanistic insights from molecular dynamics simulations confirm that selective Na⁺ interaction induces differential ion migration, generating a streaming potential; this understanding is essential for optimizing hydrovoltaic efficiency in real-world brine applications.