A use, as antimicrobial material, of semicrystalline nano- and/or microfibrillated cellulose to which silver nanoparticles are attached, the silver nanoparticles being present in a weight amount strictly greater than 1% and strictly less than 20% relative to the total weight of said cellulose, the material being obtained with a process including at least one step of microwave irradiation of an aqueous dispersion of semicrystalline nano- and/or microfibrillated cellulose supplemented with at least one silver salt, in the presence of a reducing agent. An antimicrobial composition including such an antimicrobial material and to the application thereof for forming an antimicrobial film or coating, in particular for an article for food-processing.
