Cu- and Zn-based 1D MOFs as hosts to encapsulate Eu(iii) for tuning white light emission†

In this work, the synthesis of luminescent Eu(III)-encapsulated Cu MOF and Zn MOF is reported as efficient materials with tunable light-emitting properties. The MOFs were derived from a salen-type Schiff base with multiple N donors and additional –OH groups for holding Eu(III). The Eu(III)-encapsulated MOFs, Eu–Cu MOF and Eu–Zn MOF hybrids, were characterized using FTIR, TGA, PXRD, FE-SEM, and XPS analyses. The hybrids emitted a wide range of light in the visible and near-IR range. The International Commission on Illumination (CIE) coordinates of Eu–Cu MOF and Eu–Zn MOF hybrids were (0.25, 0.35) and (0.31, 0.29), with correlated colour temperature (CCT) magnitudes of 9896 K and 6719 K, respectively. Additionally, when the outer epoxy resin layer of LEDs was uniformly coated with Eu–Cu MOF and Eu–Zn MOF, green light and near-white light were emitted, respectively, at a voltage of 3 V. Thus, this work provides a new synthetic approach for the development of white light-emitting host–guest materials.