Caption
Under the microscope, these strange little blue ice cubes mirror the fragility of the world around us. However, these tiny blocks of ice apparently adrift on the ocean are in fact crystals of metal-organic frameworks (MOF), nanostructured materials renowned for their exceptional porosity. Here, they are undergoing a process that is the exact opposite of an ice sheet breaking up: deposited on a silicon wafer, they will first grow and then combine with their neighbours to produce the smoothest, most homogeneous layer possible, completely free of cracks. The gaps seen between the crystals are only a phase in the development of this uniform layer. The future membrane will act as a molecular sieve able to filter specific gases (hydrogen for the automotive industry, methane, CO , etc.) or catalyse chemical reactions. This image is a winner of the 2021 La preuve par l'image (LPPI) competition.
