A nanoparticle of a decomposition product of a transition metal aluminum hydride compound, a transition metal borohydride compound, or a transition metal gallium hydride compound. A process of: reacting a transition metal salt with an aluminum hydride compound, a borohydride compound, or a gallium hydride compound to produce one or more of the nanoparticles. The reaction occurs in solution while being sonicated at a temperature at which the metal hydride compound decomposes. A process of: reacting a nanoparticle with a compound containing at least two hydroxyl groups to form a coating having multi-dentate metal-alkoxides.