Direct decarbonation of micrometer-scale layered double hydroxides without morphology damage

A direct decarbonation route without obvious morphology damage was developed for large micrometer-scale layered double hydroxides (LDHs). First, we synthesized pure, hexagonal-shaped LDHs with lateral dimension of micrometer-size by the recently reported urea hydrolysis method. Then, using HNO3–NaNO3 mixed solution, the obtained LDH with carbonate anions in the interlayer (LDH_CO3) was directly decarbonated to its nitrate form, LDH_NO3, its morphology and particle size were still unchanged. Compared with the recently published two-step decarbonation method, the direct decarbonation reported herein is very convenient.