Knitting Aryl Network Polymers-Incorporated Ag Nanoparticles: A Mild and Efficient Catalyst for the Fixation of CO2 as Carboxylic Acid

A simple and scalable method for synthesizing silver nanoparticles supported on the framework of mesoporous knitting aryl network polymers (KAPs) has been developed. With the benefits from its mesoporous texture and the stabilizing effect of phosphine compounds in the matrix, the silver precursor can be efficiently introduced into the KAPs framework, which results in a nanosize distribution of Ag (ca. 4.1 nm) supported on KAPs (Ag/KAPs-P) with narrow particle size distribution and homogeneous dispersion after simple reduction step. The as-obtained metal small-sized Ag/KAPs-P catalyst is particularly active for the direct carboxylation of terminal alkynes with CO2 into carboxylic acid at low temperature and atmospheric pressure. Moreover, this Ag/KAPs-P catalyst also shows high stability under the reaction conditions, and it can be recycled at least five times without significant loss of activity, suggesting its great potential application in the heterogeneous conversion of CO2 into carboxylic acid.