Sensitization of Er³⁺ Infrared Photoluminescence Embedded in a Hybrid Organic‐Inorganic Copolymer containing Octahedral Molybdenum Clusters

Abstract

Luminescent hybrid copolymers are obtained by copolymerizing in bulk methylmethacrylate with a methacrylic acid (MAC) solution containing [n‐Bu4N]2[Mo6Br8(MAC)6], and aliquots of an Er(TMHD)3 complex (TMHD for 2,2,6,6‐tetramethyl‐3,5‐heptanedione) solution. This leads to novel homogeneous and transparent hybrid materials in which the Er3+ infrared luminescence at 1.55 μm, a standard wavelength for telecommunication applications, is up to six time more intense in the presence of Mo6 clusters when samples are irradiated at 476.5 nm. This work demonstrates the outstanding potential of Mo6 clusters, compounds obtained by high‐temperature solid‐state synthesis, in the design of functional hybrid materials via soft chemistry routes.

Luminescent metal nanoclusters: controlled synthesis and functional applications

“…Since the energies of these bands are similar for Mo 6 Cl 14 2− and Mo 6 Br 14 2− , it is believed that both highest occupied and lowest unoccupied molecular orbitals are largely metal centered [61]. Other researchers have revealed that Mo 6 NCs can be integrated with other material systems, such as semiconducting quantum dots [46], silica [47] and copolymer [48]. In an earlier effort, Grasset et al [46] presented the preparation and characterization of a novel organosol and solid state nanocomposite, namely (( n -C 4 H 9 ) 4 N) 2 Mo 6 Br 14 @ZnO, by using an original and simple bottom-up process.…”

“…Recently, a simple method to obtain Mo 6 –PMMA copolymer samples within which Mo 6 clusters keep their intrinsic luminescence properties has been reported [48]. These emissive properties have been used successfully to sensitize Er 3+ complex emission in the infrared region and within the polymer matrix.…”

“…In recent years, employing state-of-the-art quantum chemistry codes, relatively accurate prediction and explanation of the optical properties of a broad range of NCs have been realized [8–12]. A broad range of luminescent metal NCs composed of gold (Au) [5–7, 13–27], silver (Ag) [12, 25–36], copper (Cu) [25, 35, 37, 38], platinum (Pt) [25, 39, 40], bismuth (Bi) [11, 41–45], molybdenum (Mo) [46–48] or mixed metals [49–51] have been successfully fabricated using diverse top-down or bottom-up approaches. Compared with other counterparts, Au and Ag NCs have attracted more attention and have been intensively studied over the past decade.…”

From Cs2Mo6Cl14 to Cs2Mo6Cl14·H2O and Vice Versa: Crystal Chemistry Investigations

“…Face-capped Mo 6 X i 8 X a 6 units containing octahedral molybdenum clusters are the basic buildings blocks of many inorganic solid state compounds, hybrid frameworks and nanomaterials [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. Formation of Mo 6 cluster occurs at high temperatures via solid state reactions.…”

Syntheses, Structures, and Luminescence Properties of New Octahedral Cluster Complexes with Terminal Phenolate Ligands: [K(H2O)(CH3OH)3]2[Ph4P]2[M 6Cl12(O–C6H4–F)6] (M = Nb, Ta; Ph = phenyl)

“…They are the first hexanuclear niobium and tantalum cluster compounds showing luminescence properties. They might have high potential for photochemical applications [34][35][36][37][38].…”