One-pot synthesis of hydrophobic and enhanced red-emitting CaCO3:Eu3+ phosphors

Abstract

Enhanced red-emitting CaCO₃:Eu³⁺ phosphors were in situ prepared using the carbonization method in the presence of sodium oleate. It has been proved that the introduction of sodium oleate can endow the products with a hydrophobic surface, which makes the products exhibit good compatibility with plastics or other polymers. Remarkably, the addition of sodium oleate can also enhance the red emission intensity of CaCO₃:Eu³⁺ phosphors greatly compared to that of the common CaCO₃:Eu³⁺ phosphors. The enhancement is attributed to two functions of sodium oleate. One function is that sodium oleate can avoid OH ligands and/or crystal water molecules attached on the surface of CaCO₃ particles; the other function is that Na⁺ ions can supply effective charge compensation.