A Hierarchical MnO ₂ ‐Polypyrrole‐Graphene Oxide Hydrogel as a Photothermal Platform for Synergistic Solar Steam Generation, Disinfection, and Energy Harvesting

Utilizing abundant solar energy to produce clean water, eliminate pathogens, and generate electricity is a transformative route for resolving the concomitant global emergencies in water and energy shortages. Photothermal energy conversion emerges as distinct and compelling approach. However, most current photothermal active materials remain constrained within low evaporation efficacy, narrow antibacterial ability, and inefficient energy utilization. Herein, we introduce a hierarchical MnO 2 ‐polypyrrole‐graphene oxide (PPy@MnO 2 @GO) hydrogel designed as a multifunctional 3D‐photothermal material. Hydrogel structure integrates PPy's broadband solar absorption and high photothermal conversion capacity with MnO 2 nanosheet's catalyst benefits within GO's porous hydrophilic framework. This synergistic combination supports ultra‐rapid solar steam generation at 1.44 kgm −2 h −1 evaporation capacity, 75°C rise in water temperature within 1 min, accompanied by highly effective antibacterial activity (99% inactivation within 3h) and consistent thermoelectric power generation (2.7 mA, 0.5 mW cm −2 ). Furthermore, permeable hydrogel network enables quick water conduction, optimal heat confinement, and satisfactory ion exclusion to provide sustainable operation ability even within saline and polluted media. Long cycling performance evaluation further validated its long‐term stability and multifunctionality, upholding efficacy across repeated cycles. By integrating water purification, sterilization, and power generation within a solitary adaptive PPy@MnO 2 @GO hydrogel, it stands as potential next‐generation photothermal framework toward sustainable energy and environmental technology.