Solvothermal growth of Mg-MOF-74 films on carboxylic functionalized silicon substrate using acrylic acid

Abstract

The fabrication of metal-organic framework (MOF) films on solid substrates is challenging due to poor wettability and lack of sufficient reactive functional groups on the surface, which prevents the stable attachment and growth of MOF films. For this reason, many studies have been conducted to directly grow MOF films on solid substrates such as metals, metal oxides and ceramics using polymer or functional groups. In this work, silicon (100) substrates were functionalized with carboxylic functional groups using a mixture of acrylic acid and hydrofluoric acid through hydrosilylation process. Mg-MOF-74 films formed on silicon substrates by 24 hours of solvothermal synthesis exhibited high surface areas (965 m2/g) and high CO2 gas capture behavior (186 cm3/g). This approach allowed the direct growth of Mg-MOF-74 films on silicon substrates by solvothermal synthesis. Further, this work provides a concept for the surface treatment to form sufficient reactive functional groups based on carboxylic acid on silicon substrates.