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 HNO_3-NaNO_3 mixed solution,the obtained LDH with carbonate anions in the interlayer（LDH_CO_3） was directly decarbonated to its nitrate form,LDH_NO_3,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.
