Room-temperature Preparation of covalent Organic Framework Membrane For Nanofiltration.

The uniquely tunable nature of covalent organic frameworks (COFs), whose pore size and stability can be controlled by choosing diverse organic building blocks and linkage types, makes COFs potential candidates for the membrane separation. Therefore, the preparation of membranes with effective separation efficiency based on COFs has aroused great interest among researchers. Although solvothermal approach has been the most popular method for the preparation of COF membranes, fabricating COF membranes at room temperature (RT) would provide a simple and captivating strategy for separation membranes. Herein, we have successfully obtained a P-COF membrane on porous alumina substrate at RT, showing 99.7% rejection of rhodamine B and excellent water permeance up to 52 L m -2 h -1 bar -1 , which can effectively purify wastewater. P-COF was directly grown on alumina to form the composite membrane, which enhanced the mechanical strength of COF membrane and avoided the risk of damaging the membrane structure during the transfer process of self-standing membrane. Moreover, P-COF membrane was grown at RT, which was more energy efficient than the conventional solvothermal method. Thus, it is of great significance to obtain COF membranes with excellent nanofiltration performance in a simple and mild condition to alleviate environmental and energy concerns. This article is protected by copyright. All rights reserved.