A Europium(III) Complex Embedded in a Polysulfone Host Matrix: A Flexible Film with Temperature‐Responsive Ratiometric Behaviour. Issue 12 (4th December 2020)

• Record Type: Journal Article
• Authors: Outis, Mani; Leal, João P.; Avó, João; Monteiro, Bernardo; Pereira, Cláudia C. L.
• Is Part Of: ChemPlusChem. Volume 85:Issue 12(2020)
• Page Start: 2629
• Page End: 2635
• Publication Date: 2020-12-04
• Subjects: Lanthanides -- luminescence -- phase transitions -- thermal response -- thin films; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cplu.202000710
• Languages: English
• ISSNs: 2192-6506

Abstract

Abstract: An emissive europium(III) complex [C2 mim][Eu(fod)4 ] (1 ; C2 mim=1‐ethyl‐3‐methyl‐imidazolium; fod=1, 1, 1, 2, 2, 3, 3‐heptafluoro‐7, 7‐dimethyloctane‐4, 6‐dionate) was prepared. The complex shows ratiometric thermal behaviour up to 155 °C. These unusual temperature‐dependent properties arise from a solid‐solid phase transition that promotes increased contact between the anion and the cation, affecting the emission profile of the emissive anion in two different ratiometric relations. A ultrabright and flexible emissive photopolymer film was obtained using polysulfone (PSU ) as the host matrix of 10 % (w/w) of 1, that also induced changes on the lanthanide emissive profile with temperature. A temperature‐responsive luminescent film 1/PSU is sensitivr to heating between 100 and 155 °C. Also, the emission lifetime of 1 was not affected by confinement in PSU, while its emission quantum yield was reduced from 82 to 59 %. Abstract : An unusual thermally activated anion–cation interaction, characteristic of the anion [Eu(fod)4 ] −, occurs in the complex [C2 mim][Eu(fod)4 ], which shows two different types of ratiometric thermal behaviour arising from solid‐solid phase transitions. Its confinement in polysulfone resulted in a new stimuli‐responsive thin luminescent film, which was senstive to heating up to temperatures between 100 and 155 °C.