18733-98-7Relevant articles and documents
Molecular design with silicon core: Toward commercially available hole transport materials for high-performance planar p-i-n perovskite solar cells
Xue, Rongming,Zhang, Moyao,Xu, Guiying,Zhang, Jingwen,Chen, Weijie,Chen, Haiyang,Yang, Ming,Cui, Chaohua,Li, Yaowen,Li, Yongfang
, p. 404 - 413 (2018)
Organic hole transport layers (HTL) play a very important role for realizing high performance and low-cost planar p-i-n perovskite solar cells (pero-SCs). In this work, we synthesized two X-shaped organic HTL materials, Si-OMeTPA and SiTP-OMeTPA, with silicon cores and triphenylamine (TPA) derivative branches. This molecular design strategy can substantially simplify synthetic procedures making them available for reducing device costs. This is particularly applicable for Si-OMeTPA since it can be synthesized by two steps from commercial raw materials showing a total yield of over 60%. This molecularly designed Si-OMeTPA possesses advantages of high thermal stability, high crystallinity with a long range ordered lamellar structure, and excellent hole mobility. The resulting HTL can also facilitate the sequential growth of high-quality perovskite films, giving a significantly enhanced photovoltaic performance with a best power conversion efficiency of 19.06%, which is one of the highest PCE among the planar p-i-n pero-SCs to date. In addition, the devices exhibit negligible hysteresis, good reproducibility, and stability. To the best of our knowledge, this is the first example of an easily synthesized HTL material in planar p-i-n pero-SCs that shows superior performance relative to the well-known poly(bis(4-phenyl)(2,4,6-trimethylphenyl)amine) (PTAA) HTL.
Hyperbranched blue-light-emitting alternating copolymers of tetrabromoarylmethane/silane and 9,9-dihexylfluorene-2,7-diboronic acid
Liu, Xue-Ming,He, Chaobin,Hao, Xiao-Tao,Tan, Li-Wei,Li, Yanqing,Ong
, p. 5965 - 5970 (2004)
The first soluble hyperbranched tetrahedral polymers were prepared by Suzuki coupling polycondensation reaction between tetrabromoarylmethane/silane and 9,9-dihexylfluorene-2,7-diboronic acid at low concentrations. The polymers exhibited high thermal stability with their decomposition temperatures (T dS) in the range 352-449°C. The polymers emitted blue light highly efficiently in both solution and the solid state. The photoluminescence quantum efficiencies of the polymers in THF solution were in the range 73-99%, and those in thin films were 38-82%. The film PL spectra of the polymers exhibited similar spectral patterns to those determined in solutions, with 1-8 nm red shift in their emission maxima and 0-8 nm increase in their full width at half-maximum (fwhm) values being observed. No long wavelength excimer-like emissions at 500-600 nm, which were typical for polyfluorenes due to their self-aggregation in the solid state, were observed. Thus, the polymers were less prone to self-aggregation in the solid state due to their hyperbranched structures. A double-layer polymer light-emitting diode (PLED) device with a configuration of ITO/P_EDOT/polymer/LiF/Ca/Ag was fabricated. The device showed bright blue emission peaking at 415 nm with an external quantum efficiency of 0.6% and a turn voltage at 6.0 V. The synthetic simplicity, good solubility and solution processability, high PL quantum efficiencies in solution and the solid state, and nonaggregating property in the solid state would make the present polymers a novel class of blue emitters.
Synthesis of Nanostructured Organosilicon Luminophores Based on Phenyloxazoles
Skorotetcky,Borshchev,Cherkaev,Ponomarenko
, p. 25 - 41 (2019/04/27)
A series of nanostructured organosilicon luminophores (NOLs) composed of a central 1,4-bis(5-phenyl-1,3-oxazol-2-yl)benzene (POPOP) acceptor chromophore and various peripheral p-terphenyl and 2,5-diphenyl-1,3-oxazole donor fragments have been synthesized for the first time using van Leusen reaction and direct palladium-catalyzed C-arylation of oxazole ring. Due to different functionalities of the silicon branching centers, NOLs with different donor-acceptor ratios have been obtained. The synthesized structures are expected to possess good optical characteristics for use in photonics and optoelectronics.
Tetrahedral Tetrakis(p-ethynylphenyl) Group IV Compounds in Microporous Polymers: Effect of Tetrel on Porosity
Uptmoor, Andrea C.,Geyer, Florian L.,Rominger, Frank,Freudenberg, Jan,Bunz, Uwe H. F.
, p. 448 - 454 (2018/06/04)
Three Sonogashira–Hagihara polymerization protocols were applied for the synthesis of conjugated microporous polymers (CMPs) by using group IV tetra(p-ethynylphenyl) monomers with 1,4-diiodobenzene or 1,4-dibromobenzene. The optical properties and surface areas of the CMPs were compared and related to the preparation conditions and the geometry of the tetrahedral building block as obtained after X-ray analysis. In each series, surface areas decreased—independently from the chosen parameters of catalyst, base, and solvent—from carbon-centered CMPs (1595 m2 g?1) to silicon-, germanium-, and tin-centered (649 m2 g?1) networks.
