Technologies

CNR-ISTEC develops geopolymer composites for thermostructural applications, such as: self-supporting cavities; thermal and acoustic insulation; thermal and fire barriers; high temperature coatings and damping; molds and cores for foundry; foams and refractory linings. Geopolymers are chemically bonded materials at T <300 ° C. Being inorganic polymers without water in the structure, they tolerate high temperatures: they are incombustible, do not emit gas or fumes and do not explode.

Molecular doping (MD) is a doping method based on the use of liquid solutions. The dopant precursor is in liquid form and the material to be doped is immersed in the solution. During the immersion process, the molecule containing the dopant atom is deposited on the surface of the material forming a self-assembled monolayer, that is, ordered and compact. Through a subsequent heat treatment, the molecule decomposes and the dopant diffuses.

The invention is a synthetic method to prepare colloidal nanomaterials of V-VI-VII semiconductors that do not contain toxic elements. This is the first method for the synthesis of mixed anion nanomaterials without toxic elements at large, which permitted to obtain, among others, bismuth chalcohalide nanocrystals that are arguably considered as one of main candidates to be the next big thing for light energy conversion.

Geopolymers belong to the class of chemically bonded ceramics: they are synthesized at low temperatures and are eco-friendly, as besides the low consolidation temperature required by the process they can be produced from secondary raw materials and industrial waste of various kinds, thus reducing the energy demand and the environmental impact of the entire production cycle. Materials such as fly ash, steel mill slag, biomass ash, sludge and silt, extractive residues, mineral and ceramic powders, organic or inorganic waste fibers, plastics, etc.