Hydrothermal Synthesis of Layered Double Hydroxides Doped with Holmium, Thulium and Lutetium

For the first time, nickel-aluminum layered double hydroxides containing holmium, thulium or lutetium cations were successfully synthesized via the coprecipitation method followed by hydrothermal treatment. X-ray diffraction data show the formation of hydrotalcite-like structures with the absence of impurity phases. The presence of lanthanides is confirmed by energy-dispersive X-ray spectrometry. Assumed empirical formulae for these compounds are [Ni0.796Al0.193Ho0.011] [(NO3)0.204·yH2O], [Ni0.808Al0.178Tm0.015] [(NO3)0.193·yH2O] and [Ni0.765Al0.219Lu0.016] [(NO3)0.235·yH2O]. These novel layered compounds demonstrate the fundamental ability of doping hydrotalcite-like compounds with any lanthanide cation, which gives rise to the synthesis of new materials with specific properties.