Layered rare-earth hydroxide nanosheets(down to~3 nm thick)of Ln2(OH)5NO3·nH2O(NO3--LLnH,Ln=Y0.95Eu0.05)were successfully synthesized in one step via coprecipitation at 4-5 ℃ under pH~8.The interlayer NO3-was found to be free ions and can be fully replaced with SO42-to yield Ln2(OH)5(SO4)0.5·nH2O(SO42--LLnH).Characterizations via XRD,FE-SEM,and T-IR found that the anion exchange did not bring about any appreciable change to the 2-dimensional crystallite orphologies but basal spacing of the crystal structure shrank from~0.846 nm to 0.823 nm owing to the indirect coordination of SO42-to the Ln3+ ions.