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The synthesis and characterization of a series of monodisperse pyrene-modified oligocarbazoles is described. The carbazoles are linked by ethynylene through the 3- and 6-positions to form stable zigzag molecular backbone.

A new magnetism-assisted chemical vapor deposition method is devised to produce and synthesize branched or iron-capsulated carbon nanotubes (CNTs). The coalescence or the division of the catalyst particles is found to being promoted by the external magnetic field, providing such CNTs.

A diabatic model and a first-principle direct method is used to investigate the carrier transport properties of the highly efficient organic light-emitting materials 1,1,2,3,4,5-hexaphenylsilole (HPS) and 1-methyl-1,2,3,4,5-pentaphenylsilole (MPPS). The theoretical studies have shown that the electron mobility is very close to that of the hole and the carrier mobilities for MPPS are larger than those for HPS.

Study is conducted to demonstrate that linearly condensed fused-ring pentathienoacene represents a new class of p-channel semiconductor with good stability owing to their large band gap. The fused ring thiophene shows high mobility of 0.045 cm(super 2)/V s while this stable organic semiconductor similar to pentacene would be extremely valuable for the application in organic electronics.

The structures, photoluminescence, and charge carrier transport properties of 1,1-disubstituted 2,3,4,5-tetraphenylsiloles as well as the effect of substituents on these characteristics are investigated. The single crystals of the three siloles involving 1,1-dimethyl 2,3,4,5-tetraphenylsilole, 1-methyl-1, 2,3,4,5-pentaphenylsilole and 1,1,2,3,4,5-hexaphenylsilole were grown and their crystal structures are determined by X-ray diffraction.

The structures and electroluminiscent properties of bis2-(2-hydroxyphenyyl)benzothiazolate are investigated. The molecular structure of an anhydrous [Zn(BTZ)(sub 2)](sub 2) obtained by sublimation is determined by X-ray single-crystal diffraction.

A study on the incorporation of amine group in SBA-15 through the co-condensation of tetraethoxysilane (TEOS) with aminopropylsilane (APTES) under a strong acidic condition is presented. The results demonstrate the effect of APTES present in the initial synthesis mixtures on the formation of SBA-15 mesostructure such as structural ordering, pore size, and surface area.

A detailed study on the formation of cobalt-basic-carbonate compounds [Co(OH)x-(CO3)0.5(2-x).nH2O] with dimensional and morphological controls using two complementary precipitation methods is reported. Results reveal that Co3O4 nanorods can be synthesized with this method in a small diameter regime of 20-40 nm.

Study of the self-assemble of Hs-Pc and its application as a hole injection material in OLEDs is presented. Phthalocyanine monolayer-modified gold substrates showed high efficiency as anodes for organic light-emitting diodes.

Two soluble phthalocyanine derivatives, 2, 9, 16-tri(tert-butyl)-23-(10-hydroxydecyloxy) phthalocyanine (1) and 2, 9, 16-tri(tert-butyl)-23-(10-hydroxydecyloxy) copper phthalocyanine (2) were used as semiconductor layers in organic thin-film transistors (OTFTs) based on their Langmuir - Blodgett (LB) films. The highest occupied molecular orbital and the lowest unoccupied molecular orbital were determined, and the energy band diagram of their OTFT can be deduced by the cyclic voltammetric measurements.

Synthesis, characterization, and solvatochromic properties of two asymmetrically substituted dicyanovinyl heterotetracenes are demonstrated. Both experimental and computational results suggested that the two heterotetracenes have low-lying lowest unoccupied molecular orbital and hence might find potential use as n-type or bipolar organic semiconductors for organic electronics.

A template chemical vapor deposition method was developed for scalable synthesis of few-layer graphene ribbons (FLGRs) with controlled morphologies. The realized controllable and scalable synthesis of graphene provides an application of graphene in nanoelectromechanic (NEM) switches and to conduct valuable studies for both the scientific and the practical applications of graphene.

The synthesis, crystal structure and photophysical properties of a new series of ladder-type heteroacenes containing both pyrrole and furan rings, 5,6-disubstituted diindolo[3,2-b:4,5-b']thiophenes (DITs) are described. The size of substituents and the molecular dipole moment have effects on the solid-state packing simultaneously, and the S-S interactions enhance the electronic transport between molecules.

The design and fabrication of a series of organic semiconductors which exhibit excellent field-effect properties due to strong intermolecular interactions and proper molecular energy levels is described.

The synthesis and characterization of a series of highly fluorescent, pyrene-modified oligo(2,7-fluorene ethylene)s is reported. The complexes could be used as optoelectronic material to study fluorescent structure-property relationship of fluorene derivatives.

A new class of high-performance organic field effect transistor (OFET) semiconductor based on perylo[1, 12,b,c,d]thiophene (PET) is analyzed. The analysis has shown that the extraordinary solid-state packing arrangement with the likelihood of double-channel fashion induced by marked S...S interactions have contributed to the high performance.

The outstanding electronic properties of low-cost organic transistors and invertors that use the M-TCNQ (M-Ag or Cu)-modified Ag or Cu source-drain (S-D) electrodes in bottom-contact configurations are described. It is shown that the contact resistance and energetic mismatch typically observed with the low-cost bare electrodes in the petacene bottom-contact organic field-effect transistors (OFETs) can be properly removed.

A study reports the fabrication of organic field-effect transistors (OFETs) with 1-imino nitroxide pyrene as the semiconductor layer. The device can be operated within low voltage and shows p-type FET characteristics with excellent performance.

Four X-shaped oligothiophenes with different conjugation length are investigated as novel electron donors in single-layer bulk-heterojunction solar cells. The simple organic single-layer bulk-heterojunction photovoltaic cell with four X-shaped oligothiophenes as novel donors and PCBM as an acceptor are fabricated.

The fabrication and characterization of field-effect transistor based on an individual multiwalled nitrogen-doped carbon nanotube is reported. Temperature dependence of two-terminal transport experiments suggests that transport is dominated by thermionic emission and tunneling through a 0.2 eV Schottky contact barrier.

Four donor-acceptor functionalized molecular materials with symmetrical structures are synthesized and investigated for their use in optoelectronic applications. These materials exhibit multifunctional properties, such as a red light-emitting behavior and a large photovoltaic effect.

Photoluminescence (PL) and electroluminescence (EL) properties of a poly(p-phenylenevinylene) (PPV) derivative cantaining crown ether (C-PPV) are investigated. The PL quantum yield as high as 90% in solution and a temperature independence are observed.

A large-scale synthesis of well-aligned carbon nanotube films with controllable diameter and length are reported. A simple technique is developed to measure anisotropic electrical transport properties of as-aligned carbon nanotube films.

Production of omega-3polyunsaturated fatty acids concentratesfrom oil of Schizochytrium limacinumwas optimizedto obtain the highest omega-3 polyunsaturated fatty acid (ω-3PUFA)enrichment ratio. In this process, the content of docosapentenoicacid (DPA), the content of docosahexenoic acid (DHA) in the finalproduct, the percentage recovery of the heavy phase, and the ω-3PUFAenrichment ratio were optimized. Single-factor experiments were carriedout to study the effects of evaporator temperature, feeding rate,feeding temperature, and roller speed. A central composite designwas used to optimize technological conditions. Under optimum conditions,the highest ω-3PUFA enrichment ratio (92.98%) was obtained atan evaporator temperature of 110.4 °C, a feeding rate of 78.7mL/h, a roller speed of 350 rpm, a feeding temperature of 80 °C,and an operating pressure 10 Pa. [ABSTRACT FROM AUTHOR]

Two new dendronized nonlinear optical (NLO) polyfluorenes were synthesized with high azo-chromophore loading density by the introduction of high generation chromophore dendrons on the side chains. Thanks to the advantages of Sharpless’ click chemistry reaction, the dendrons were conveniently bonded to the backbone of polyfluorene with the conversion of 100%, although they were really very bulky. The new-formed triazole rings in the dendrons acted as suitable isolation groups to minimize the strong dipole−dipole interactions among the polar chromophore moieties to improve NLO effects, according to the results obtained from UV−vis spectra and order parameters. All the polymers were well characterized and exhibited good solubility, high thermal ability, wide optical window, and large NLO effects (up to 106.0 pm/V). In addition, the tested NLO results of these dendronzied polymers demonstrated a deviation from the dipolar frustration that typically limits the NLO effect in conventional chromophore/polymer composite materials, indicating that the frequently observed asymptotic dependence of electro-optic activity on chromophore density may be overcome through rational design. [ABSTRACT FROM AUTHOR]