A hydroxy-containing three dimensional covalent organic framework bearing silver nanoparticles for reduction of 4-nitrophenol and degradation of organic dyes

Abstract

Covalent organic frameworks (COFs), as a novel platform for the synthesis of metal nanoparticles, display abundant properties of adjustable porosity, high crystallinity and large surface area. In particular, three-dimensional (3D)-COFs are unique skeletons with greater surface areas, numerous easily accessible active sites and interpenetrating channels compared to 2D-COFs. These eminent properties of 3D-COFs are very beneficial for anchoring metal nanoparticles, and effectively restrict the size and growth of nanoparticles, enhancing the catalytic performance. In this study, we prepare hybrid nano-materials (denoted as AgNPs-3D-COF) based on Ag nanoparticles and a hydroxy functional 3D-COF. The strong coordination between OH groups and metal Ag and finite aperture generate uniform and small size Ag nanoparticles. When applied to the catalytic reduction of 4-nitrophenol and the degradation of organic dyes, namely methylene blue and Congo red, AgNPs-3D-COF delivers high activity and enduring cycling stability. We expect that this study can offer a strategy for constructing advanced heterogeneous metal nanoparticle catalysts and accelerate the advancements of 3D-COFs.