Chaaban Maya, Chi Yu-Chieh, Worku Michael, Zhou Chenkun, Lin Haoran, Lee Sujin, Ben-Akacha Azza, Lin Xinsong, Huang Chen, Ma Biwu
Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States.
Department of Scientific Computing, Florida State University, Tallahassee, Florida 32306, United States.
Inorg Chem. 2020 Sep 21;59(18):13109-13116. doi: 10.1021/acs.inorgchem.0c01256. Epub 2020 Aug 31.
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 MMLCT 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.
具有强铂-铂相互作用的双核铂（II）配合物是一类有趣的发光材料，其光物理性质可通过有机配体和铂-铂间距以多种方式进行调控。虽然已经开发出许多具有可调发射的双核铂（II）配合物，但实现高光致发光量子效率（PLQE）仍然具有挑战性且备受关注。在此，我们报道了一系列由具有不同体积的噻唑-2-硫醇盐配体桥连的双核2,4-二氟苯基吡啶铂（II）配合物的合成与表征。发现这三种配合物的铂-铂间距较短，范围在2.916至2.945 Å之间。强铂-铂相互作用导致在450至500 nm之间出现明显的金属-金属到配体的电荷转移（MMLCT）吸收，并在橙/红区域产生强烈的MMLCT发射。新配合物的PLQE在溶液中为2-31%，在固态中为26-100%。这些配合物在卤代溶剂中也表现出优异的稳定性。
