A Universal Cl‐PEDOT Coating Strategy Based on Oxidative Chemical Vapor Deposition toward Solar‐Driven Multifunctional Energy Management

Abstract Converting renewable solar energy into manageable thermal energy is significant for diverse applications. Nevertheless, integrating multifunctional solar‐to‐heat coating on various substrates and achieving large‐scale manufacture remains a challenge. Herein, Cl − doped poly(3,4‐ethylenedioxythiophene) (Cl‐PEDOT) coating on multiple substrates is successfully created using oxidative chemical vapor deposition (oCVD) without to be restricted to the changeable substrate surface chemistry (e.g., wettability), sizes as well as dimensions (2D–3D). Partial Cl − doping and spontaneously formed microstructures can remarkably enhance near‐infrared absorption and hydrophilicity of coating. The Cl‐PEDOT coating manifests many advantages: universality, scalability, low‐cost, high efficiency, and stability. When used for solar steam generation, all Cl‐PEDOT coated substrates represent reinforced evaporation performance. The universality makes it possible to optimize the evaporator performance by structural design. Structural design as optimized energy flow enables the pyramid array wood‐based evaporator to set an evaporation record (≈1.19 kg m −2 h −1 , ≈91%) under the weak‐light (0.5 sun). Moreover, a greenhouse and a crude‐oil cleaner are designed to achieve eco‐friendly, energy‐saving solar‐driven heating/dehumidification, and crude‐oil recovery without additional energy input. This study reveals that well‐designed oCVD is a simple and straightforward way to engineer lightweight and thermally insulating polymers into multifunctional solar‐to‐thermal composites toward diverse solar‐driven applications.