ABSTRACT
We demonstrate the conceptual advantage of using metal-organic frameworks (MOFs) for the creation of a polymetallic material that contains several different near-IR-emitting lanthanide cations and operates as a barcode material with unique luminescence properties. By choosing the ratio of lanthanide salts used during the synthesis, we can control the ratio of lanthanide cations present in the resulting material. We have demonstrated that the emission intensity of each of the different lanthanide cations is proportional to its amount in the MOF crystal, resulting in unique spectroscopic barcodes that depend on the lanthanide cation ratios and compositions.
Subject(s)
Electronic Data Processing/methods , Lanthanoid Series Elements/chemistry , Luminescent Agents/chemistry , Organometallic Compounds/chemistry , Electronic Data Processing/instrumentation , Luminescent Measurements , Materials Testing , Models, Molecular , Molecular Structure , Spectroscopy, Near-Infrared/methodsABSTRACT
The design of metal-organic frameworks (MOFs) incorporating near-infrared emitting ytterbium cations and organic sensitizers allows for the preparation of new materials with tunable and enhanced photophysical properties.
Subject(s)
Organometallic Compounds/chemistry , Ytterbium/chemistry , Cations/chemistry , Crystallography, X-Ray , Molecular Structure , Physical Phenomena , Spectroscopy, Near-InfraredABSTRACT
A strategy to sensitize and protect near-infrared (NIR) emitting Nd3+ and Yb3+ is presented. Combining protection provided by the inorganic matrix of NaYF4 nanocrystals and sensitization from tropolonate ligands capped on their surface, the lanthanide cation centered luminescence was observed through the ligand excitation. The extended lanthanide luminescence lifetimes indicate the success of this strategy.
Subject(s)
Fluorides/chemistry , Nanoparticles/chemistry , Neodymium/chemistry , Organometallic Compounds/chemistry , Tropolone/analogs & derivatives , Ytterbium/chemistry , Yttrium/chemistry , Ligands , Luminescent Measurements , Microscopy, Electron, Transmission , Molecular Structure , Nanoparticles/ultrastructure , Spectrophotometry, Infrared , Tropolone/chemistryABSTRACT
The electronic structure of CdSe semiconductor nanocrystals has been used to sensitize Tb3+ in solution by incorporation of Tb3+ cations into the nanocrystals during synthesis. Doping of luminescent Tb3+ metal ions in semiconductor nanocrystals utilizes the positive attributes of both species' photophysical properties, resulting in a final product with long luminescence lifetimes, sharp emission bands, high absorptivities, and strong resistance to decomposition. This strategy also helps protect the lanthanide cations from nonradiative deactivation from C-H, N-H, and O-H oscillators of solvent molecules or traditional organic lanthanide ligands, leading to long Tb3+ luminescence lifetimes. This new type of nanomaterial synergistically combines the photophysical properties of nanocrystals and Tb3+.
