Benincasa hispidas-inspired pore-gradient aerogel with integrated water and thermal management for highly efficient solar vapor generation and water purification.

• The PPY/PG is small-pores at top region and large-pores at the bottom region. • The long-standing trade-off between water supply and heat loss was surmounted. • The PPY/PG shows evaporation rate of 2.49 kg m−2h−1 and solar efficiency of 96.3 %. Engineering the pore structure of evaporator to effectively integrate water and thermal management is critical for efficient solar-driven interfacial vapor generation. Here, inspired by the unique structure of Benincasa hispidas , a bioinspired pore-gradient aerogel was fabricated for the first time. Experiments and numerical simulations reveal that the unique anisotropic porous structure of aerogel, which consists of small-pores at top region and large-pores at bottom region, enabling it to maximize the heat gains from the sunlight and localize the generated heat while provide adequate water supply concurrently. Under solar illumination (1 kW m−2), the fabricated aerogel can achieve a high evaporation rate of 2.49 kg m−2h−1, and the calculated energy efficiency is approximately 96.3 %, which is comparable to most of state-of-the-art evaporators. Additionally, with this aerogel employed, effective purification toward various undrinkable water can be achieved. This work derives from nature, providing us a design blueprint to integrate water and thermal management in a bulky material, and it is expected to advance one step further toward the design and practical application of high-performance solar evaporators. [ABSTRACT FROM AUTHOR]