Revealing Hierarchical Structure and Topochemistry of Bamboo for Efficient Solar Steam Generation

Global freshwater scarcity demands sustainable and cost-effective solutions. Solar-driven interfacial steam generation offers a promising approach, yet the performance optimization of biomass-based evaporators remains constrained by a limited understanding of their hierarchical structures. Herein, we present a comprehensive investigation of the multiscale architecture and topochemistry of bamboo, elucidating structure-property correlations between its inner and outer samples. Building on these insights, bamboo-based solar evaporators were fabricated via the in situ polymerization of polypyrrole (PPy), achieving superior solar absorption and thermal localization. The optimized bamboo-based evaporator delivers an outstanding evaporation rate of 2.996 kg·m –2 ·h –1 under 1 sun irradiation, offering a sustainable solution to global water and energy challenges. Moreover, the produced condensate meets WHO guidelines for drinking water, confirming its suitability for practical seawater desalination applications. This work provides new insights into the rational utilization of bamboo for high-performance photothermal materials and advances sustainable strategies for solar-driven water purification.