Energy transfer between Eu³⁺ and Nd³⁺ in near-infrared emitting β-triketonate coordination polymers

Abstract

Isomorphous β-triketonate-based lanthanoid polymers containing tris(4-methylbenzoyl)methanide (mtbm) and Rb+ with formula {[Ln(Rb)(mtbm)4]2}n (Ln = Eu3+ and Nd3+) have been synthesised and structurally characterised. The photophysical properties for the Nd3+ complex presented relatively long lifetimes and high quantum yields in comparison with analogous β-diketonate complexes. Mixed lanthanoid complexes were also formed and their luminescence properties studied, with effective sensitisation of the 4F3/2 of Nd3+via the 5D0 of Eu3+, which is to the best of our knowledge the first example of Eu3+ to Nd3+ sensitisation in a structurally defined coordination complex or polymer.

Excited State Properties of Lanthanide(III) Complexes with a Nonadentate Bispidine Ligand

“…These numbers result in an intrinsic quantum yield of 0.41 and 0.34, respectively, giving sensitization efficiencies of 0.71 and 0.97, respectively. While the value in the solid state is moderate, as observed for other Eu III complexes,[ 73 , 74 ] the value in water is remarkably high, where typically enhanced quenching by the solvent is observed [73] and highlights the intense luminescent properties of these compounds in solution.…”

Accessing Lanthanide‐to‐Lanthanide Energy Transfer in a Family of Site‐Resolved [LnIIILnIII′] Heterodimetallic Complexes

“…[54][55][56][57] There are, however,s ome remarkable exampleso fh omo-or heterometallic Ln-to-Ln ET studies taking place within discretem olecules. [35,48,[58][59][60][61][62][63][64][65][66] Most of them are conducted in solution,w ith polydentate ligandsi nt he presence of two different lanthanide ions. [67][68][69] In many of these systems, there is little-to-no control over the location of each Ln III in the molecular scaffold, which is mainly dictated by statisticals peciation.…”

Energy Transfer in Metal–Organic Frameworks and Its Applications

“…Indeed, an example of a mixed Eu 3+ /Nd 3+ ‐based MOF with efficient sensitization from the 5 D 0 of Eu 3+ to the 4 F 3/2 of Nd 3+ was formulated. [ 66 ] When compared to pure Nd 3+ ‐MOFs, the enhanced optical properties of the mixed‐Ln MOFs indicate the occurrence of the f–f EnT bridging effect between the ligands and the Nd 3+ ions. In this vein, Zeng et al designed a series of bimetallic Ln‐MOFs, namely, M 1− x Nd x L 2 (M = Eu, Tb, and Dy, 0 < x < 1, L = 2,5‐pyridinedicarboxylate), [ 67 ] and used the EnT processes from the visible‐emitting M 3+ ions to the NIR‐emitting Nd 3+ ions to color‐tune the red, green, and blue wavelength regions.…”