Easy and environmentally friendly synthesis of MOF-2

Abstract

One of the pioneering metal organic framework material, called MOF-2 and having the formula Zn(bdc) 1 still continues awakening interest amongst the scientific community2·3 in spite of its layered character. However, their synthesis methods are either experimentally complicated' or in two steps through the transformation of MOF-12• Here, we describe the preparation of a high-quality MOF-2 under environmentally friendly conditions, including room temperature, absence of any amine or any other pH-controller, partially substitution of the harmful organic solvent (N,N-dimethylformamide) by water, and by simply mixing linker and metal sources, the latter being zinc acetate, carefully selected as a function of their solubility in the solvent mixture. The effect of the ratio of the two solvents and the different parameters that determine the preparation of MOF-2 have been studied. The optimum ratio of the Zn(OAc)z.4H 20 to H2bdc is 1.74 and the DMF to H20 is 3. The so-synthesized MOF-2 has been characterized using powder X-ray difftaction (Fig. la), thermal gravimetric analysis (Fig. lb), N2 adsorption/desorption and scanning electron microscopy (Fig. 1c), all of them supporting the good quality of the material.