Conversion of copper carbonate into a metal-organic framework

Abstract

The preparation of porous metal–organic frameworks (MOFs) at industrial scales requires careful selection of the metal precursor to ensure the sustainability of the synthetic process, in terms of both the environmental impact and cost. The use of earth abundant minerals is attractive for this purpose, provided that they are sufficiently reactive under the conditions of MOF formation. In this work, we investigate the use of copper carbonate and its naturally occurring counterparts, malachite and azurite, as precursors for the synthesis of Cu3(BTC)2 (HKUST-1; BTC3– = 1,3,5-benzenetricarboxylate). Using a water/ethanol solution of copper carbonate and H3BTC, HKUST-1 was obtained at room temperature within 3 h, as confirmed by a suite of characterization techniques. The identity of the products was determined by the reaction conditions, highlighting the importance of optimizing the synthetic parameters. When prepared under optimized conditions, HKUST-1 synthesized here showed analogous performance characteristics to materials obtained by traditional solvothermal methods; thus, our results confirm that high-quality samples of MOFs can be easily derived from mineral precursors.