Water‐dispersible Hollow Microporous Organic Network Spheres as Substrate for Electroless Deposition of Ultrafine Pd Nanoparticles with High Catalytic Activity and Recyclability

Microporous organic networks (MONs) have been considered as an ideal substrate to stablize active metal nanoparticles. However, the development of highly water-disperible hollow MONs nanostructures which can serve as both the reducing agent and stabilzer is highly desirable but still challenged. Here we report a template-assisted method to synthesize hollow microporous organic networks (H-MONs) spheres using silica sphere as hard template and 1,3,5-triethynylbenzene as the building blocks through Glaser coupling reaction. The obtained water-dispersible H-MONs spheres bearing sp- and sp2-hybridized carbon atoms possess highly conjugated electronic structure and show low reduction potential, which can serve as the reducing agent and stabilizer for electroless depositon of highly dispersed Pd clusters to form Pd/H-MONs spherical hollow nanocomposite. Benefitting from their high porosity, large surface area and excellent solution dispersibility, the as-prepared Pd/H-MONs hollow nanocomposite exhibit a high catalytic performance and recyclability toward the reduction of 4-nitrophenol.