Oxidative Intercalation Route to Co-Ni LDHs and Their Exfoliation to Unilamellar Nanosheets

Abstract

A topochemical route was introduced to synthesize highly crystallized hexagonal microplatelets of Co-Ni LDHs. Treating brucite-like Co-Ni hydroxides prepared by homogeneous precipitation with excessive bromine in acetonitrile promoted partial oxidization of Co²⁺ into Co³⁺ and the formation of Br^--intercalated Co-Ni LDHs inheriting the hexagonal morphology. The nitrate-intercalated samples could be exfoliated into unilamellar nanosheets on contact with formamide.