Multi-Emissive Lanthanide-Based Coordination Polymers for Potential Application as Luminescent Bar-Codes

Abstract

Isostructural lanthanide-based coordination polymers that are obtained by reactions in water of a lanthanide chloride and the sodium salt of 5-methoxyisophthalate (mip 2− ) have the general chemical formula [Ln 2 (mip) 3 (H 2 O) 8 •4H 2 O] ∞ with Ln = Nd−Er except Pm plus Y (symbolized by [Ln 2 (mip) 3 ] ∞ ). Some of these homo-lanthanide compounds present very high luminescence brightness. The weak intermetallic energy transfer between lanthanide ions observed in these compounds allows the design of hetero-lanthanide coordination polymers with tunable luminescence properties. A molecular alloy that involved six different lanthanide ions (Nd 3+ , Sm 3+ , Eu 3+ , Gd 3+ , Tb 3+ , Dy 3+ ) has been prepared and its luminescent properties have been studied. This compound, under a unique irradiation wavelength (λ exc = 325 nm), exhibits almost 20 emission peaks in both the visible and the NIR regions at room temperature. This unprecedented richness of the emission spectrum could be of great interest as far as luminescent barcodes are targeted.

A new praseodymium-based coordination polymers with 1,10-phenantroline and glutarate ligands: Synthesis, crystal structure and luminescent properties

“…Lanthanide-based coordination polymers have attracted much attention because of their fascinating crystal structures [1][2][3] and their interesting magnetic [4][5][6] and luminescent properties [7][8][9][10]. The design of lanthanide coordination polymers is based on the size and the rigidity of the ligands as well as on their ability to participate to inter-molecular interactions (hydrogen-bonds, π-stacking interactions…).…”

Encoding Multilayer Complexity in Anti‐Counterfeiting Heterometallic MOF‐Based Optical Tags

“…Without a powerful excitation source, they require sensitizers in order to produce emissions bright enough to detect. In many cases, organic molecules are used to provide this sensitization through the antenna effect [5c, 7a, 9] …”

“…An ideal optical tag should possess complex, difficult‐to‐counterfeit properties, including: i) combined overt and covert signatures created using tunable optical properties capable of concomitant emission in the ultraviolet (UV), visible, and/or NIR ranges; ii) unique fluorescence lifetime features that facilitate encoded signatures as an additional layer of complexity; iii) distinct compositional and/or structural properties to allow orthogonal confirmation of identity. Numerous studies of tag materials address one of these three sources of complexity, [2b, 5c, 10] but studies that combine multiple encoding methods are far more rare [11] …”

“…RE‐based MOFs are emerging as promising versatile materials for anticounterfeiting tags. Studies that examine RE‐MOF tags focus on enriching the emission spectra through incorporation of multiple metals or multiple domains within the crystals [5c, 10a, 21] . Additionally, the inherent porosity in MOFs has been utilized via the inclusion of photoswitchable quenching molecules, allowing the tag features to be selectively revealed [22] .…”

Understanding the Stability Trend Along Light Lanthanide Complexes with an Ehtylenediamine‐Type Ligand: A Quantum Chemical Study

“…Since 1980s, more and more attention has been paid on lanthanide (Ln) elements, due to their excellent properties and colorful potential applications . However, selective extraction of the Ln(III) ions is still a difficult task, since lanthanide ions possess similar atomic radii, chemical reactivity, and some other chemical properties .…”