Three-Dimensional Wood-Inspired Bilayer Membrane Device Containing Microchannels for Highly Efficient Solar Steam Generation.

A three-dimensional solar steam generation device with a high water evaporation rate and excellent structural stability was developed and characterized. The design consisted of a bilayer membrane composed of polyacrylonitrile (PAN) and PAN/graphene oxide (GO) segments and contained vertically aligned porous structures similar to that of wood. This distinctive design was used to improve the water evaporation rate by increasing the light absorption and specific surface area. The prepared bilayer membrane exhibited excellent water wicking and flux, and it could continuously supply water from the bottom of the solar steam generation device to the top surface. The device's performance was evaluated by exposing the PAN/GO surface to artificial sunlight with a density of 1, 5, and 10 kW m-2. The water evaporation rate and steam generation efficiency for the PAN and PAN/GO bilayer membrane were found to be 2.27 kg m-2 h-1 and 92.63% at a power density of 1 kW m-2, respectively. Owing to its facile fabrication, hierarchical pore structure, excellent mechanical and water wicking, and high efficiency, the special bilayer composite device has great potential for solar steam generation and desalination applications in resource-limited settings.