Europium and terbium-doped lanthanum hydroxycarbonate and lanthanum oxycarbonate nanoparticles were fabricated under two different reaction conditions using lanthanide acetate and urea as the starting materials. The photoluminescence properties of these hydroxycarbonate and oxycarbonate particles, and of their colloidal suspensions in water, were studied. The Eu^{3+ 5}D₀→⁷F_J and Tb^{3+ 5}D₄→⁷F_J emission spectra and the luminescence lifetimes in the two carbonate matrices were measured. Terbium-doped cerium oxycarbonate particles were synthesized, and the energy transfer process from Ce³⁺ to Tb³⁺ was investigated. The synthesis of lanthanum and cerium oxycarbonates was also carried out in the presence of stabilizing ligands: glucose and fructose. The influence of these ligands on the structure and luminescence was explored.