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Three novel AuI polyynes have been prepared in high yield by copolymerization between an AuI complex precursor and different ethynyl aromatic ligands. The investigation of their photophysical behavior has indicated that forming polyynes through polymerization not only maintains the high transparency of the corresponding AuI polyynes similar to those of their corresponding small molecular AuI acetylides, but also effectively enhances their triplet (T1) emission ability. Critically, owing to their enhanced T1 emission ability, all the AuI polyynes exhibit a stronger optical power limiting (OPL) ability against a 532 nm laser than the corresponding small molecular AuI acetylides. The AuI polyynes based on fluorene and triphenylamine ligands show even better OPL performance than the state-of-the-art OPL material C60, indicating their great potential in the field of laser protection. More importantly, in a prototype OPL device made by doping the fluorene-based AuI polyyne into a polystyrene (PS) solid matrix, substantially improved OPL activity has been observed compared with that in the solution, demonstrating its great potential for practical application. All these results have provided a new strategy to achieve a balance between high OPL activity and good transparency for OPL materials, representing a valuable attempt towards developing new OPL materials with high performance to cope with the key problems in the field of nonlinear optics. [ABSTRACT FROM AUTHOR]

Two homoleptic thiazole-based IrIII phosphorescent emitters, Ir-3Tz1F and Ir-3Tz2F, with fluorinated 2-phenylthiazole-type ligands were designed and prepared. Their thermal stability, and photophysical and electrochemical properties, as well as electroluminescent (EL) performances in both monochromic OLEDs and solution-processed WOLEDs were investigated. When doped in monochromic OLEDs made by vacuum deposition, Ir-3Tz1F gave the maximum EL efficiencies with ηL of 56.2 cd A−1, ηext of 15.8% and ηp of 50.2 lm W−1. Critically, solution-processed WOLEDs based on Ir-3Tz1F with three primary colors could achieve an excellent trade-off among the stable balanced white EL spectra, a high EL efficiency and a high color rendering index (CRI). The optimized solution-processed WOLED exhibited very attractive EL efficiencies of 33.4 cd A−1, 16.5% and 30.6 lm W−1, while maintaining both a high CRI of ca. 80 and very stable Commission Internationale de L’Eclairage (CIE) coordinates in a wide driving voltage range from 4 V to 11 V. [ABSTRACT FROM AUTHOR]

Three Pt(ii) acetylides have been prepared by coupling trans-[PtCl2(PBu3)2] to ethynyl aromatic ligands with electron-withdrawing phenylsulfonyl units in high yields (＞85%). The investigation of their photophysical behavior has shown that the unique conjugation-breaking configuration of the –SO2– linker in the phenylsulfonyl units can afford a very short cut-off wavelength (λcut-off) of ＜390 nm to the Pt(ii) acetylides, furnishing excellent transparency of these compounds. Critically, the triplet quantum yields (ΦP) of the prepared Pt(ii) acetylides can be effectively enhanced from 0.52% to 15.92% through increasing the number of fluorine substituents on the phenylsulfonyl units in the organic ligands. Benefiting from their enhanced ΦP, the phenylsulfonyl-based Pt(ii) acetylides can exhibit comparable or even better optical power limiting (OPL) performance against 532 nm lasers than the state-of-the-art OPL material C60, indicating their great potential in the field of laser protection. All of these results have provided a new strategy to achieve consistency between high OPL ability and good transparency for OPL materials, representing a valuable attempt for coping with key problems in the field of nonlinear optics. [ABSTRACT FROM AUTHOR]