NH2-UiO-66 Coated with Two-Dimensional Covalent Organic Frameworks: High Stability and Photocatalytic Activity

The poor stability and low catalytic activity of NH 2 -UiO-66 in basic solutions require the reactions to be conducted in acidic solutions, which seriously hinders its potential photocatalytic application. Herein, we report that NH 2 -UiO-66 coated with two-dimensional covalent organic frameworks (COFs) via imine bond connection presents not only high photocatalytic activity but also high stability and adaptability to the solution environment. The NH 2 -UiO-66/COF hybrid material was fabricated through the Schiff base reaction of NH 2 -UiO-66 with 4,4′,4″-(1,3,5-triazine-2,4,6-triyl)trianiline (TAPT) and 2,4,6-triformylphloroglucinol (TP). The hybrid material showed high stability in an alkaline environment, with only 4.7% of NH 2 -UiO-66 decomposed after the photocatalytic reaction. The optimum photocatalytic H 2 evolution rate was 8.44 mmol·h –1 ·g –1 when triethanolamine was used as an electron-donating agent. The results presented here illustrate the possibility for effectively improving both the photocatalytic performance and stability of NH 2 -UiO-66 by coupling with COFs.