An ultralight material that simultaneously combines remarkably
rapid water transportation, highly efficient photothermal conversion,
and excellent thermal insulation is highly desired for solar-driven
interfacial desalination but was challenging. In this work, inspired
by the unique natural structure of wood, we developed an ultralight
aerogel by ice-templated synthesis as an integrated interfacial evaporator
for solar-driven water production. The interior features vertically
aligned biomimetic microscale channels facilitating rapid transportation
of water molecules, while an improved photothermal interface allows
high solar absorption and conversion via nonradiative relaxation and
molecular vibrations. The biomimetic aerogel is ultralight with a
density as low as 0.06 g/cm3, especially its fabrication
is size- and shape-programmable as a whole and easily scalable. Additionally,
the outstanding thermal insulation of the aerogel focuses heat precisely
at the evaporation interface, reducing ineffective heat loss, while
the uniformly distributed large-sized channels promote the dynamic
convection of high concentration salt ions on the evaporator surface.
Consequently, the evaporator shows broadband light absorption of 92.7%,
leading to a water evaporation rate reaching 4.55 kg m–2 h–1 under 3 simulated solar irradiations, much
higher than that of other reported evaporators with randomly distributed
pores. This work provides new insight into advanced hybrid aerogels
for highly efficient and durable solar-driven interfacial desalination
systems.