title: New route toward nanosized crystalline metal borides with tuneable stoichiometry and variable morphologies.
abstract: Herein we highlight for the first time the ability to tune the stoichiometry of metal boride nanocrystals through nanoparticle synthesis in thermally stable inorganic molten salts. Two metal-boron systems are chosen as case studies: boron-poor nickel borides and boron-rich yttrium borides. We show that NiB, Ni4B3, Ni2B, Ni3B, and YB6particles can be obtained as crystalline phases with good selectivity. Anisotropic crystallization is observed in two cases: the first boron-rich YB4nanorods are reported, while boron-poor NiB nanoparticles show a peculiar crystal habit, as they are obtained as spheres with uniaxial defects related to the crystal structure. Crystallization mechanisms are proposed to account for the appearance of these two kinds of anisotropy at the nanoscale.
authors.affiliation: Sorbonne Universités-UPMC Univ. Paris 06, CNRS, Collège de France, Laboratoire de Chimie de la Matière Condensée de Paris, 11 place Marcelin Berthelot, 75005 Paris, France. david.portehault@upmc.fr clement.sanchez@upmc.fr.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Gouget
authors.forename: Patricia
authors.initials: P
authors.lastname: Beaunier
authors.forename: David
authors.initials: D
authors.lastname: Portehault
authors.forename: Clément
authors.initials: C
authors.lastname: Sanchez