纤维素基多元协效仿生水收集材料的结构设计、制备与性能

为解决淡水匮乏问题，研制具有雾中取水功能的水收集材料已成为高分子材料领域的研究热点之一。但受限于设计原理，当前研究尚无法兼顾水汽收集过程中水汽捕获、液滴融合、液滴运输和液体收集这四个核心环节，水收集效率较低，严重限制了该类材料的应用，成为其进一步发展亟待解决的科学问题。本项目提出将沙漠甲虫、猪笼草、水稻叶和仙人掌刺在水汽捕获、液滴快速清除、液体定向运输和促进液滴融合等方面的特性融入材料设计中，采用二/多元协效仿生策略构建具有亲水/润滑图案化表面的纤维素基集水材料。通过在润滑表面构筑不同形态的亲水点阵或槽状结构，考察亲水结构的形态差异及在润滑表面比例对液滴运输和水收集性能的影响，并基于液滴凝结与运输的动力学研究，阐明亲水图案结构构筑对四个环节的协效调控机理；通过材料的表面图案结构优化，研制出性能优异且可长效使用的纤维素集水材料。本项目可为推动纤维素材料的功能化研究提供新思路和科学借鉴。

With the growth of the world economy and the increase in population, human demand for water continues to increase. At present, 3.6 billion people are potentially experiencing water scarcity for at least one month per year, and this population may increase to 4.8−5.7 billion by 2050. Reclaiming water from available sources in clean and efficient ways and seeking alternative water sources have thus become greatly significant to overcome the water scarcity crisis. Inspired by natural plants and creatures that can collect water from air, mimic multifunction systems with fog harvesting and vapor condensation properties have attracted increasing attention in the recent years. However, limited by the design mechanisms, the four processes of water harvest, water vapor capture, droplet fusion, droplet transport and liquid collection, cannot be overall considered in current researches, resulting in the insufficient water collection efficiency as well as limiting the applications of such materials. To address the issue, in this project, we propose to incorporate the features of desert beetles, pitchers, rice leaves and cactus needles into material design, developing hydrophilic/slippery patterned cellulose-based films with water harvesting function by a dual/multiple synergistically biomimetic strategy. Different hydrophilic dot arrays and groove-structures will be constructed on slippery surfaces. The effects of the pattern shapes and content of hydrophilic domains on the water harvesting process will be investigated. The dynamic processes of droplet condensation and transport will be monitored and analyzed. The relevant mechanism for synergistically controlling the four processes will be disclosed. By optimizing the structures of the patterned surfaces, cellulose-based water harvesting materials with high-performance will be obtained. The above researches are capable of providing new thoughts and scientific basis for functionalization of cellulose materials.