Nanocellulose aerogel prepared using discarded cotton textiles: For constructing water evaporation and self-cooling thermoelectric systems

In agricultural production, the substantial consumption of water and electricity resources is an urgent issue that needs to be addressed.In this work, we address this challenge by repurposing discarded cotton fabric and employing a unidirectional ice templating freezing technique to construct a cellulose hydrophilic aerogel featuring a biomimetic structure with unidirectional vertical channels, hereafter referred to as UVC-aerogel. This innovative material facilitates the conversion of low-grade waste heat (LGWH) into both water resources and electrical energy.The UVC aerogel exhibits remarkable evaporation performance, achieving an efficient evaporation rate of 9.18 kgm- 2h- 1, while demonstrating significant resistance to salt accumulation. Moreover, the evaporation effect synergistically enhances its thermoelectric power generation capacity. Through integration with a self-cooling open thermoelectric battery system, the UVC aerogel capitalizes on the concentration gradient formed within the evaporation system to augment the Seebeck coefficient (6.86 mVK- 1) and power density (0.015 Wm- 2K- 2).This work present a green and sustainable solution to the water and electricity challenges encountered in agriculture, carrying substantial implications for both environmental conservation and agricultural advancement.