Affiliation:
1. State Key Laboratory of Silicon and Advanced Semiconductor Materials Department of Polymer Science and Engineering Zhejiang University 310058 Hangzhou China
2. Dalian Ecological and Environmental Affairs Service Center Dalian Municipal Bureau of Ecological Environment 116023 Dalian China
Abstract
AbstractDeveloping materials to harvest water from the air is of great importance to alleviate the water shortage for people living in arid regions, where the annual average relative humidity (RH) is lower than 0.4. In this work, we report a general nitrogen atom incorporation strategy to prepare high‐performance covalent organic frameworks (COFs) for water harvesting from the air in arid areas. A series of COFs, namely COF‐W1, COF‐W2, and COF‐W3 were developed for this purpose. Different contents of nitrogen were embedded into COFs by incorporating pyridine units into the building blocks. With the increasing content of nitrogen from COF‐W1 to COF‐W3, the inflection points of their water isotherms shift distinctly from RH values from 0.65 to 0.25. Significantly, COF‐W3 exhibits the lowest inflection point at a low RH value of 0.25 and reaches a high uptake capacity of 0.28 g g−1 at 25 °C with a low hysteresis loop. Moreover, the gram‐scale COF‐W3 retains its high performance, which renders it more attractive in water harvesting. This work demonstrates the feasibility of this nitrogen incorporation strategy to acquire high‐performance COFs as water harvesters in the future.
Funder
National Natural Science Foundation of China
National Key Research and Development Program of China
Fundamental Research Funds for the Central Universities
Subject
General Chemistry,Catalysis,Organic Chemistry