Ultrablack Poly(vinyl alcohol)‐Graphite Composite Xerogel with Vertically Arranged Pores for Highly Efficient Solar Steam Generation and Desalination

Ultrablack materials have attracted wide attention due to their high light absorbance and efficient photothermal conversion used in the field of solar steam generation alleviate drinking water crisis. Herein, ultrablack low‐cost poly(vinyl alcohol)‐graphite composite xerogels (PGCXs) that vertically arranged pores thermal conductivities are fabricated. The PGCX‐50% shows (95.44%), good wettability, a evaporation rate 1.24 kg m −2 h −1 under 1 sun illumination when coupled two dimensional (2D) evaporator. To further improve performance, is switched three (3D) evaporator by rotating it. Under illumination, 3D has highest 3.80 , which 3.07 times 2D evaporator, its larger area higher surface at subambient temperature. Finally, heatsink‐like designed up 9.54 achieved with wind energy. rates PGCX even concentrated brines ensure great potential for production seawater desalination.