Dysprosium(III) carbonate is an inorganic compound with the chemical formula Dy2(CO3)3. It is a white, paramagnetic solid.
Properties An amorphous tetrahydrate exists, stable in air up to near the decomposition temperature. It progressively loses water upon heating and is directly converted to dysprosium oxide (Dy2O3) by dehydration and carbonate calcination: Dy2(CO3)3·xH2O → Dy2O3 + xH2O + 3 CO2
An orthorhombic kozoite-type DyCO3OH forms under hydrothermal conditions, and a poorly crystalline tengerite-type Dy2(CO3)·2-3H2O remains stable at ambient temperature.
Preparation Dysprosium(III) carbonate can be prepared by reacting a soluble dysprosium salt such as dysprosium(III) chloride with sodium carbonate, forming a white gel-like precipitate. The flow rate of the Dy(III) solution and the reactor temperature affect the particle size of the product.
Another method involves the hydrolysis of dysprosium trichloroacetate in a homogeneous phase reaction: 2 Dy(Cl3CCOO)3 + (x+3)H2O → Dy2(CO3)3·xH2O + 3 CO2 + 6 CHCl3 Carbon dioxide and chloroform are formed as byproducts in this reaction.
It can also be prepared by passing carbon dioxide through a suspension of dysprosium hydroxide or oxide in water. The conversion is slow and may not produce a pure product. The reaction is fast with higher yields if supercritical CO2 at high pressure is used instead.
Uses It can be used as a photocatalyst for the degradation of methyl orange under ultraviolet light.
Related compounds The crystal structures of the hydroxide carbonate (DyOHCO3) and another basic carbonate (Dy2O2CO3) have been determined. They can be prepared by hydrothermal synthesis involving the reaction of dysprosium(III) chloride and carbon dioxide with caesium carbonate and potassium carbonate respectively.
The dysprosium tetracarbonate complex [C(NH2)3]4[Dy(CO3)4(H2O)](H3O)·13H2O has been characterized by single-crystal X-ray diffraction. It can be prepared by treating saturated guanidinium carbonate solution with dysprosium nitrate.
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