A scalable, low-cost and robust photo-thermal fabric with tunable and programmable 2D/3D structures towards environmentally adaptable liquid/solid-medium water extraction

As a renewable and sustainable resource, solar energy exploited to conduct interfacial water evaporation has attracted considerable attention. However, conventional photo-thermal materials mainly focus on the issues of energy efficiency and multifunctionality, the lack of scalable, low-cost, flexible and washable features severely restrict the application from labs to industrialization. Significantly, owing to the low utilization of the spatial volume of the conventional two-dimensional (2D) evaporators, the development of editable and controllable 3D structures toward improved energy efficiency is highly desirable. Inspired by the traditional sewing clothes, herein, a functional photo-thermal fabrics with excellent scalable, washable and inexpensive features is designed to realize tunable and programmable 2D/3D structures, which enable the favorable in-plane and out-of-plane water extraction from liquid/solid medium. Since the polypyrrole (PPy) has favorable photo-thermal, stable features and strong interactions with the fibrous cotton, an in situ tunable oxypolymerization strategy was employed to construct PPy modified cotton fabric. The facile and robust approach enables the formation of a large-area PPy-modified cotton (PMC), which could function as a 2D generator for well-controlled in-plane water evaporation. Furthermore, the excellent sewable and editable features of the fabrics allow the programmable integration of these functional PMC building blocks into 3D system towards high-efficient out-of-plane solar vaporization. Specifically, the 3D design can adapt the photo-thermal fabrics to diverse environments with efficient purified water collection even from sand matrix.