Engineering of Metal-Organic Frameworks/Gelatin Hydrogel Composites Mediated by the Coacervation Process for the Capture of Acetic Acid

Abstract

A novel strategy is proposed to synthesize metal-organic framework (MOF)-gelatin bionanocomposites by taking profit of the thermo-reversible character of gelatin and the liquid-liquid phase separation process, that is, coacervation. This enables the formation of bionanocomposites based on a series of chemically stable Zr4+dicarboxylate MOFs (UiO-66 and MOF-801) differing by their hydrophilic-hydrophobic balance and their chemical functionality. Bionanocomposites with homogeneous and uniform distribution of MOF particles in the gelatin matrix as well as a high MOF loading (up to 90%) without compromising their porosity were prepared as a result of an excellent physico-chemical matching between MOFs and gelatin. Finally, this series of bionanocomposites were shaped into films or monoliths, and they have shown high performance for the selective adsorption of acetic acid in the presence of humidity. These composites can be regarded as highly efficient adsorbents for cultural heritage preservation.