Preparation And Performance Of High Efficiency Interfacial Solar-Driven Evaporation Device By Polymer/Fiber

With the rapid growth of global population and rapid economic social development,global freshwater consumption has increased,and the freshwater crisis has become one of the greatest threats to global sustainable development.Seawater desalination is an available solution to the problem.However,currently,most seawater desalination technologies require a large amount of upfront engineering investment and energy consumption during production.The overall cost is high.Solar energy,as an almost infinite renewable energy source,is a promising way to drive seawater desalination and wastewater treatment.The interfacial solar driven evaporation system has excellent performance due to its ability to absorb solar energy through photothermal conversion materials and convert it into thermal energy,while limiting the flow of heat through devices and materials,and only using heat to heat the surface water in the overall water.Therefore,there are many studies at this stage.However,there are still some problems in the interface solar driven evaporation system,such as slow evaporation efficiency,low light to heat conversion,and so on.To address the above issues,we select polymers as the main photothermal conversion materials,and use fiber cloth as its base material and combine them.Under the premise of cost control,structural design is used to improve light absorption capacity and water evaporation rate.The specific research content is as follows:（1）In this article,we use surface self-polymerization to deposit and polymerize dopamine hydrochloride on a fiber fabric substrate under alkaline conditions,using polyamine（PDA）as a photothermal conversion material.Subsequently,through the reducibility of PDA itself,silver ions were reduced in silver nitrate solution under alkaline conditions.Silver nanoparticles（Ag NPs）were introduced into the system together with PDA as photothermal conversion materials.The water evaporation rates under two-dimensional（2D）and three-dimensional（3D）conditions were studied and explored,achieving a high evaporation value of 2.36 kg m^-2 h^-1 in 3D structural design.A horizontal comparison between woven fabrics and non-woven fabrics as substrate materials was made,and it was determined that compared to woven fabrics,non-woven fabrics have advantages in both microstructure and overall evaporation capacity.（2）In this article,for the first time,we demonstrate a highly efficient three-dimensional（3D）mirror-assisted and quadrangular pyramid-shaped solar-thermal water evaporation system for high-yield and long-term desalination of seawater and brine water,which consists of a 3D solar-thermal architecture on the basis of polypyrrole-coated non-woven fabrics（PCNF）,a3D mirror array,a self-floating polystyrene foam layer,and a tail-like PCNF for upward transport of water.The 3D solar-thermal architecture enables multiple solar light reflections to absorb more solar energy,while the 3D mirror-assisted solar light enhancement design can activate the solar-thermal energy conversion of the backside of the 3D PCNF architecture to improve the solar-thermal energy conversion efficiency.Crucially,selective accumulation of the precipitated salts on the backside of the concave pyramid-shaped architecture is realized,ensuring a favorable salt-resistant feature.The 3D mirror-assisted solar-driven water evaporation system achieves a high water evaporation rate of4.75 kg m^-2 h^-1under 1-sun irradiation only and exhibits a long-term desalination stability even when evaporating high-salinity brine waters,demonstrating its great applicability and reliability for high-yield solar-driven desalination of seawater and high-salinity brine waters.