Thiazol-2-thiolate-Bridged Binuclear Platinum(II) Complexes with High Photoluminescence Quantum Efficiencies of up to Near Unity

Maya Chaaban; Yu-Chieh Chi; Michael Worku; Chenkun Zhou; Haoran Lin; Sujin Lee; Azza Ben-Akacha; Xinsong Lin; Chen Huang; Biwu Ma

doi:10.1021/acs.inorgchem.0c01256

Thiazol-2-thiolate-Bridged Binuclear Platinum(II) Complexes with High Photoluminescence Quantum Efficiencies of up to Near Unity

Inorg Chem. 2020 Sep 21;59(18):13109-13116. doi: 10.1021/acs.inorgchem.0c01256. Epub 2020 Aug 31.

Authors

Maya Chaaban¹, Yu-Chieh Chi², Michael Worku³, Chenkun Zhou⁴, Haoran Lin¹, Sujin Lee¹, Azza Ben-Akacha¹, Xinsong Lin¹, Chen Huang^{2

3

5}, Biwu Ma^{1

3

4}

Affiliations

¹ Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States.
² Department of Scientific Computing, Florida State University, Tallahassee, Florida 32306, United States.
³ Materials Science and Engineering Program, Florida State University, Tallahassee, Florida 32306, United States.
⁴ Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Tallahassee, Florida 32310, United States.
⁵ National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States.

PMID: 32865987
DOI: 10.1021/acs.inorgchem.0c01256

Abstract

Binuclear platinum(II) complexes with strong Pt-Pt interactions are an interesting class of luminescent materials, of which photophysical properties could be controlled via multiple ways through organic ligands and Pt-Pt distance. While a number of binuclear platinum(II) complexes have been developed with tunable emissions, achieving high photoluminescence quantum efficiency (PLQE) remains challenging and of great interest. Here we report the synthesis and characterization of a series of binuclear 2,4-difluorophenylpyridine platinum(II) complexes bridged by thiazol-2-thiolate ligands with different bulkiness. The three complexes were found to have short Pt-Pt distances ranging from 2.916 to 2.945 Å. The strong Pt-Pt interactions lead to pronounced metal-metal-to-ligand charge transfer (MMLCT) absorptions between 450 and 500 nm, and strong ³MMLCT emissions in the orange/red region. The PLQEs of the new complexes are in the ranges of 2-31% in solution and 26-100% in solid state. These complexes also exhibit excellent stability in halogenated solvents.