Dual-biomimetic synergistic structured aerogel for high-performance solar-driven water purification and power...

The scarcity of clean water drives urgent demand for sustainable purification technologies. Solar-driven interfacial evaporation is regarded as an attractive approach, yet it continues to suffer from problems of salt crystallization, mechanical weakness, and insufficient photothermal utilization. To overcome these limitations, we developed a dual-biomimetic synergistic structured nanofiber aerogel (PPMPAN) for efficient seawater purification and solar-driven power generation. The aerogel was fabricated via directional freeze-drying, producing vertically aligned channels that mimic plant water transport, thereby enhancing capillary water transport, mechanical robustness, and salt resistance. In parallel, surface modification with porous metal-organic frameworks (MOFs), polydopamine (PDA), and polypyrrole (PPy) generated a coral-inspired hierarchical architecture, which markedly improves broadband solar absorption (≈94.07 %) and interfacial hydrophilicity. The synergistic integration of tree-like channels and coral-like multiscale surfaces enables the PPMPAN aerogel to achieve efficient solar-driven water evaporation, delivering an evaporation rate of 2.60 kg m⁻² h⁻¹ under 1 sun. The aerogel maintains stable operation in 25 wt. % brine, across pH 1-13, and continuous use for 50 h. Additionally, the aerogel exhibits multifunctionality, not only purifying oily wastewater but also generating electricity under solar irradiation. This work offers a scalable and eco-friendly strategy for generation solar evaporators, tackling key challenges at the water-energy nexus.