Ju Mei,†,‡,∥ Nelson L. C. Leung,†,‡,∥ Ryan T. K. Kwok,†,‡ Jacky W. Y. Lam,†,‡ and Ben Zhong Tang*,†,‡,§ †HKUST-Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen 518057, China ‡Department of Chemistry, HKUST Jockey Club Institute for Advanced Study, Institute of Molecular Functional Materials, Division of Biomedical Engineering, State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China Guangdong Innovative Research Team, SCUT-HKUST Joint Research Laboratory, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China

Aggregation-Induced Emission: Together We Shine, United We Soar!

Luminogenic materials with aggregation-induced emission (AIE) attributes have attracted much interest since the debut of the AIE concept in 2001. In this critical review, recent progress in the area of AIE research is summarized. Typical examples of AIE systems are discussed, from which their structure–property relationships are derived. Through mechanistic decipherment of the photophysical processes, structural design strategies for generating new AIE luminogens are developed. Technological, especially optoelectronic and biological, applications of the AIE systems are exemplified to illustrate how the novel AIE effect can be utilized for high-tech innovations (183 references).

Aggregation-induced emission

-phenylenevinylene)s L4. Fluorene-Based Conjugated Polymers L4.1. Fluorene-Based Copolymers ContainingElectron-Rich MoietiesM4.2. Fluorene-Based Copolymers ContainingElectron-Deﬁcient MoietiesN4.3. Fluorene-Based Copolymers ContainingPhosphorescent ComplexesQ5. Carbazole-Based Conjugated Polymers R5.1. Poly(2,7-carbazole)-Based Polymers R5.2. Indolo[3,2-

https://ir.nctu.edu.tw:443/bitstream/11536/6508/1/000271856900020.pdf

Synthesis of Conjugated Polymers for Organic Solar Cell Applications

Aggregation-induced emission: phenomenon, mechanism and applications.

A review was presented to demonstrate a historical description of the synthesis of light-emitting conjugated polymers for applications in electroluminescent devices. Electroluminescence (EL) was first reported in poly(para-phenylene vinylene) (PPV) in 1990 and researchers continued to make significant efforts to develop conjugated materials as the active units in light-emitting devices (LED) to be used in display applications. Conjugated oligomers were used as luminescent materials and as models for conjugated polymers in the review. Oligomers were used to demonstrate a structure and property relationship to determine a key polymer property or to demonstrate a technique that was to be applied to polymers. The review focused on demonstrating the way polymer structures were made and the way their properties were controlled by intelligent and rational and synthetic design.

Synthesis of Light-Emitting Conjugated Polymers for Applications in Electroluminescent Devices

Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole

We synthesized three substituted polyacetylenes carrying 1,2,3,4,5-pentaphenylsilolyl (PS) pendants, i.e., −[HCC(PS)]n− (1), −{HCC[(CH2)9OPS]}n− (2) and −{(C6H5)CC[(CH2)9OPS]}n− (3), and succeeded in turning polymers 2 and 3 from weak luminophors into strong emitters by external stimuli of aggregation and cooling. The silolylacetylene monomers HC⋮CPS (10), HC⋮C(CH2)9OPS (11), and C6H5C⋮C(CH2)9OPS (12) were polymerized by NbCl5− and WCl6−Ph4Sn catalysts, which gave high molecular weight polymers in high yields (Mw up to ∼70 × 103 Da and yield up to ∼80%). The structures and properties of the polymers were characterized and evaluated by IR, UV, NMR, DSC, TGA, PL, EL, and nanoparticle size analyses. The polymers were thermally stable and lost little weights when heated to ∼350 °C. Whereas all the polymers were practically nonluminescent when molecularly dissolved, polymers 2 and 3 became emissive when aggregated in poor solvents or when cooled to low temperatures. Restricted intramolecular rotation or twisti...

Silole-containing polyacetylenes. Synthesis, thermal stability, light emission, nanodimensional aggregation, and restricted intramolecular rotation

Biphenyl- (Biph-) containing 1-alkynes (3 and 4) and their polymers (1 and 2) with varying bridge groups and spacer lengths were synthesized and the effects of the structural variation on their properties, especially their mesomorphism and photoluminescence behaviors, were studied. The acetylene monomers 3(3) [HC⋮C(CH2)3O−Biph−OCO(CH2)10CH3] and 4(m) [HC⋮C(CH2)mOCO−Biph−OCO(CH2)10CH3, m = 3, 4] were prepared by sequential etherization and esterification reactions of 1-alkynes. While 3(3) exhibits enantiotropic crystal E and SmB mesophases, its structural cousin 4(3) displays only a monotropic SmB phase. Enantiotropic SmA and SmB mesophases are, however, developed when the spacer length is increased to 4. Polymerizations of the monomers are effected by Mo-, W-, Rh-, and Fe-based catalysts, with the WCl6−Ph4Sn catalyst giving the best results (isolation yield up to 85% and Mw up to 59000). The polymers were characterized by IR, UV, NMR, TGA, DSC, POM, XRD, and PL analyses. Compared to 1(3), 2(3) shows a red...

Liquid Crystalline and Light Emitting Polyacetylenes: Synthesis and Properties of Biphenyl-Containing Poly(1-alkynes) with Different Functional Bridges and Spacer Lengths

Capping an indium–tin–oxide anode with a thin layer of praseodymium oxide (Pr2O3) has been found to enhance not only hole-injection, quantum, and power efficiencies but also the lifetime of organic light-emitting diode made using copper (II) phthalocyanine as the anode buffer layer, N, N′-diphenyl-N,N′ bis(3-methylphenyl-1,1′-biphenyl-4,4′-diamine as the hole-transport layer and tris-8-hydroxyquinoline aluminum as the electron-transport/emission layer. The best results have been obtained on diodes with ∼1 nm thick Pr2O3. A possible mechanism behind the improvement is discussed.

Praseodymium oxide coated anode for organic light-emitting diode

We investigate the switching bistability based on the interaction between dynamic flow and director rotation in twisted nematic liquid crystal cells. Numerical calculation shows that there exists a general type of bistable twisted director configuration. Two specific cases are verified experimentally.

Zhiliang Xie

Papers

Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole

Silole-containing polyacetylenes. Synthesis, thermal stability, light emission, nanodimensional aggregation, and restricted intramolecular rotation

Liquid Crystalline and Light Emitting Polyacetylenes: Synthesis and Properties of Biphenyl-Containing Poly(1-alkynes) with Different Functional Bridges and Spacer Lengths

Praseodymium oxide coated anode for organic light-emitting diode

Dynamic Flow and Switching Bistability in Twisted Nematic Liquid Crystal Cells