Green synthesis of a large series of bimetallic MIL-100(Fe,M) MOFs

Abstract

Here we present a scalable and green methodology to synthesize a large variety of MIL-100(Fe,M), metal-doped iron-based MOFs with high thermal stability and surface areas. Our synthesis is performed at room temperature in aqueous media and can be applied to doping with p-, d- and f-elements in oxidation states from +I to +V, therefore being highly general. The influence of the doping metal nature on the thermal and textural properties is systematically investigated. We show that large differences between the ionic radius of the doping and the templating metals does not lead to phase segregation. The incorporation of Cu(I) drastically lowers the thermal stability of MIL-100(Fe,Cu), while the incorporation of V, Al and Ti induces the formation of mesopores. Finally, we developed a PXRD-based method that can be combined with TGA to easily access the metal ratios in complex mixed-metal MOFs.