Preparation of di-boride coatings by electrophoretic deposition in nanoparticle-containing molten inorganic salts

Molten inorganic salts containing solid nanoparticles with a stable and uniform dispersion have attracted great attention as efficient heat transfer and storage materials1,2 and for catalysis for chemical reactions3-5. Electrophoretic deposition in molten inorganic salts containing nanoparticles, have not been reported in the literature, compared with the related wide investigations in aqueous and organic suspensions6,7. Here we report the possibility of electrophoretic deposition of nanoparticles in high-temperature molten salts. In molten fluorides and chlorides, cell voltages of 1.2-1.5 V below the decomposition voltage of the electrolytes, were applied to perform the electrophoretic deposition of nanoparticles (e.g., TiB2 and ZrB2) on different cathode substrates, resulting in compact and adhesive coatings with high hardness. These findings should present opportunities to synthesize additional coatings and films via the proposed process.