Dual-Emission Luminescence of Magnesium Coordination Polymers Based on Mixed Organic Ligands

摘要

Presented herein are two luminescent magnesium coordination polymers (Mg-CPs), namely [Mg-2(H2O)(2)(2-NDC)(4)(1,10-phen)(2)] (1) and [Mg-2(H2O)(1,4-NDC)(2)(1,10-phen)] (2), in which 2-NDCH = 2-naphthalenecarboxylic acid, 1,4-NDCH2 = 1,4-naphthalene dicarboxylic acid, and 1,10-phen = 1,10-phenanthroline. Based on the mixed ligands, the title compounds exhibit linker-based photoluminescence (PL) properties thanks to the unique configuration of the Mg2+ ions. The two compounds show interesting dual emission on excitation of the different luminophores of the mixed linkers. In particular, the emissions of compound 2 could be tuned from green to yellow simply by varying the excitation energies. Furthermore, 2 could be excited by using a commercial lambda = 450 nm blue LED chip to generate white-light emission, which allows the fabrication of a white-light-emitting diode (WLED) with 20 lm W-1 luminous efficacy. This work may provide a new method for designing tunable PL CPs by using the low-cost and abundant magnesium ion.