Solvothermal synthesis of La-based metal-organic frameworks and their color-tunable photoluminescence properties

摘要

A series of La-based metal-organic frameworks (La-MOFs) phosphors have been successfully synthesized by a facile solvothermal method without assistance of any surfactant or template. The results show that the ethanol volume ratio is important to obtain adjustable shape and size of La-MOFs in the synthesis process. The obtained samples possess flake-like architectures with about 3-5 urn in length. Under UV excitation, all the La-MOFs :Tb~(3+), Eu~(3+) phosphors exhibit the characteristic emissions of Tb~(3+) and Eu~(3+). Moreover, the emitting color of the as-obtained products can be acquired from green, green-yellow, yellow, yellow-orange, orange, to red owing to the efficient energy transfer (ET) between Tb~(3+) and Eu~(3+)ions. The ET efficiency of the samples was calculated, and the maximum was found about 96.84%. Furthermore, the dipole-quadru-pole interaction has been reasonable proved by the energy transfer between Tb~(3+) and Eu~(3+). These results indicated that La-MOFs:Tb~(3+), Eu~(3+) might be as a novel potential candidate as phosphors for displays and lightings.