过渡金属配位结构调控超吸水凝胶对低湿度空气水的捕获行为及机制

开发高效的吸水凝胶，实现温和条件下捕获干旱地区的气态水，是节能环保及获取淡水资源的理想形式。然而，常见的吸水材料难以直接与水分子快速耦合，因此存在吸附速率慢和脱附能耗高的问题。本项目拟通过过渡金属配位化合物的结构调控，从提升电子空轨道与孤电子对配位、相转变过程中的能量转移等独特的角度出发，揭示配位化合物的结构协同调控规律及其与水分子耦合过程中的能量转移规律。以增强对水分子的吸附动力为核心，在金属基超吸水凝胶的宏观尺度、纳米尺度和分子尺度上进行多尺度结构调控，大幅提高吸水凝胶捕获气态水并将其转化为液态水的性能。结合吸附动力检测与理论计算，深入分析配位化合物的结构形成规律和耦合水分子的物理机制，并探索单/多金属基超吸水凝胶结构与吸附量、吸附速率和脱水温度之间的关系，建立直接从低湿度空气中捕获水分子的效能评价体系。项目成果将丰富水分子气液相转变的基础理论，为极端气候条件下获取水资源开拓新的途径。

Developing a hygroscopic hydrogel to capture gaseous water at low humidity condition is an idea strategy for water generating and energy saving. However, for common materials, they are difficult to couple with water efficiency, and the inherent problem is the slowly hydration rate and highly dehydration temperature. Here, by an unique method, according to the coordination of electron empty orbits and lone electrons, we intend to integrate the energy transfer controlled transition metal complexes, and going to reveal the law of structure regulation and energy transfer in the process of coupling with water molecules. To enhance the adsorption kinetics, multi-scale structure regulations are carried out at the macro, nano, and molecular scale for our atmospheric water harvesting system. Combining with adsorption kinetic tests and theoretical calculations, we plan to analyze the formation mechanism of coordination compounds, and clarify the physical mechanism of water adsorption. We will also investigate the relationship of super hygroscopic hydrogels’ structure and adsorption capacity, adsorption rate, and dehydration temperature, and establish an evaluation system for directly moisture harvesting. We believe our results will strengthen the basic theory of gas-liquid phase transition with water molecules, and open up a new strategy to obtain water resources under extreme climate conditions.