减少CO2等温室气体的排放需要高效、可循环使用的捕获材料。用来再生捕获材料的能耗高低是决定捕获成本的重要因素。本项目以CO2固定排放源（如火力发电厂）的烟气为目标，计划从捕获材料与CO2的电子结构出发，结合宏观的兰缪尔吸附模型，设计可由光调控CO2与捕获材料的作用强度的新型吸着（吸附、吸收）模型体系。该体系结合了能跟CO2形成共价键的路易斯碱和能够光响应构象变化的偶氮骨架。通过光调节CO2--捕获材料复合物的构象，利用其顺、反构象的几何结构和局部化学环境的差异，调控CO2的吸着强度。我们希望能够利用光能减少CO2捕获的能耗，即在吸着作用强的构象下吸收CO2，然后通过光控改变构象，再在吸着作用弱的构象下释放CO2。我们将把这类模型体系引入离子液体、多孔固体等材料。同时这些模型体系有可能被用于其他酸性气体（SO2、NOx等等）的捕获。

Reducing the emission of greenhouse gases like CO2 requires efficient and reusable capture materials. The energy for regenerating the capture media is crucial to the cost of CO2 capture. In this proposal, we target flue gases from stationary CO2 sources such as coal powerplants. Starting from electronic structures of capture materials and CO2, and empolying a macroscopic Langmuir-type adsorption model, we design CO2 capture model systems with photoswitchable CO2 sorption (adsorption and absorption). The model systems feature the conjunction of Lewis bases that can covalently bond with CO2 and azo-based backbones that can switch conformations upon light stimulation. Thus by regulating the conformation of the CO2-sorbent complex, differences in structures and local chemical environments of the cis and trans conformations can be utilized. As a result, the sorption strength between CO2 and capture materials can be controlled. We hope by taking advantage of light energy, the cost of CO2 capture can be lowered, i.e., capture CO2 with the strong CO2-sorbent interacting conformation, then switch the conformation by light, and finally release CO2 with the weak CO2-sorbent interacting conformation. We will integrate these sorption prototypes into ionic liquids, porous solids, etc. Meanwhile, these models might be applied in the capture of other acidic gases (SO2, NOx, etc.).