Nanostructured particles by controlled precipitation techniques. Example of nickel and cobalt hydroxides

By controlling the conditions of homogeneous precipitation reactions, it is possible to obtain more and more complex structures from individualized nanoparticles to multi-scale micrometric particles. This is shown in the case of nickel and cobalt hydroxide. Precipitation using the combination of ammonia decomplexation and dodecylsulfate templating leads to nanostructured nickel hydroxide submicronic cylinders and flower-like cobalt hydroxide. After calcination, surfactant is removed and their respective oxides keep the original shapes. NiO nanostructured cylinders exhibit a relatively high specific surface area around 130 m²/g and a pore size around 4 nm, consistent with the observed nanostructure.