LEACHED NANOCRYSTALLINE MATERIALS, METHOD FOR MAKING THEM AND USES IN THE ENERGETIC SECTOR

摘要

The invention concerns leached nanocrystalline materials having a large specific surface area particularly useful for storing hydrogen or for making electrodes for catalysis or electrocatalysis, such as those used in fuel cells. These materials can be made by preparing a nanocrystalline material consisting of a metastable composite or alloy of at least two distinct chemical elements. To be nanocrystalline, the material should have a crystalline structure with crystals less than 100 nn. in size. The prepared nanocrystalline material is then subjected to a leaching so as to eliminate partly or totally at least one of the elements of the composite or alloy. This leaching gives the resulting material a porous structure and, hence the required large specific surface area.