Realizing Pure White Light Emission by Adjusting the Molar Ratio of Eu3+/Tb3+ in Two New Ln-Based Metal-Organic Frameworks

Abstract

Two Ln-based Metal-Organic Frameworks (MOFs), Eu-BCTC and Tb-BCTC are synthesized based on the ligand [9,9'-bicarbazole]-3,3',6,6'-tetracarboxylic acid (H4BCTC) by solvothermal method. They emit green or red light. By adjusting the molar ratio of Eu3+/Tb3+ of LMOFs, herein successfully prepared a single-phase white light emitters Eu0.075Tb0.925-BCTC with an ideal CIE coordinate of (0.33, 0.33), internal quantum yield (IQY) at 8.37% and the color temperatures of 5623K. Moreover, it has excellent performance in detecting Fe3+, Cr2O72- and CrO42-, with quenching coefficients (Ksv) at 7.403×10-5 M, 1.487×10-5 M and 3.053×10-5 M, respectively. It is an interesting development in the MOF-based white-light-emitting phosphors and fluorescence probes.

Keywords: metal-organic frameworks, white-light emitting, crystal structure, probe, solvothermal