Yongsheng Mi

Synthesis and Third-Order Nonlinear Optical Properties of Triphenylene Derivatives Modified by Click Chemistry

A series of asymmetric triphenylene derivatives containing typical D-π-A structures is successfully synthesized by means of [2+2] cycloaddition-cycloreversion click reactions. The photophysical and electrochemical properties, as well as the click reactions, are characterized by means of UV/Vis absorption spectroscopy, cyclic voltammetry, and DFT modulations. In addition, the third-order nonlinear properties, including the nonlinear absorption and the nonlinear susceptibilities, are investigated by using Z-scan techniques. A typical reverse saturable absorption-saturable absorption behavior is observed for the third-order nonlinear absorption, with the third-order nonlinear susceptibilities of the compounds being 1.05×10(-12) , -1.50×10(-12) , and -0.52×10(-12) esu, respectively.

Application of Near‐IR Absorption Porphyrin Dyes Derived from Click Chemistry as Third‐Order Nonlinear Optical Materials

Abstract Recently, third‐order nonlinear properties of porphyrins and porphyrin polymers and coordination compounds have been extensively studied in relation to their use in photomedicine and molecular photonics. A new functionalized porphyrin dye containing electron‐rich alkynes was synthesized and further modified by formal [2+2] click reactions with click reagents tetracyanoethylene (TCNE) and 7, 7, 8, 8‐tetracyanoquinodimethane (TCNQ). The photophysical properties of these porphyrin dyes, as well as the click reaction, were studied by UV/Vis spectroscopy. In particular, third‐order nonlinear optical properties of the dyes, which showed typical d‐π‐A structures, were characterized by Z‐scan techniques. In addition, the self‐assembly properties were investigated through the phase‐exchange method, and highly organized morphologies were observed by scanning electron microscopy (SEM). The effects of the click post‐functionalization on the properties of the porphyrins were studied, and these functionalized porphyrin dyes represent an interesting set of candidates for optoelectronic device components.

Pyrene-Based Small Molecular Nonlinear Optical Materials Modified by ''Click-Reaction''

Two pyrene derivatives were successfully synthesized via an efficient copper(I)-catalyzed azide alkyne 1,3-dipolar cycloaddition. The photophysical and electrochemical properties were characterized using ultraviolet-visible absorption spectra, fluorescence spectra, cyclic voltammograms and density functional theory modulations. These results showed that the symmetry structure of these derivatives formed an electron-delocalized organic system, which have larger effects in achieving a third-order nonlinear optical (NLO) response. The third-order nonlinear properties including the nonlinear absorption and the nonlinear susceptibilities investigated by Z-scan technique indicate that the title compounds can serve as a promising candidate for third-order NLO applications.

Effects of donor and acceptor on optoelectronic performance for porphyrin derivatives: Nonlinear optical properties and dye-sensitized solar cells

Typical asymmetric donor-π-bridge-acceptor(D-π-A) zinc porphyrin dyes have been synthesized, and further modified by reacting the ethynyl groups of them with click reagent through a formal [2+2] click reaction. The electronic interaction between the push and pull electronic groups and the click reaction process were investigated by UV-Vis absorption spectroscopy. The nonlinear optical(NLO) properties of the dyes were studied by the Z-scan technique and clearly reverse saturable absorption to saturable absorption(RSA-SA) transition could be observed through click reaction of the dyes with TCNE. Furthermore, the photovoltaic properties of these porphyrin dyes were reasonably explained by the J-V curve fitting based on the equivalent-circuit model as well as the comparison between the absorption and incident-photon-to-current-conversion efficiency(IPCE) spectra. Besides, these dyes with different donors or acceptors could self-assembly into different microstructures by phase transfer methodology.

Third-order nonlinear optical properties of a novel series of azobenzene liquid crystal derivatives

ABSTRACT A novel series of D-π-A bi-alkyne liquid crystal derivatives were designed and synthesized, which had typical D-π-A structures. The third-order nonlinearities of the compounds were studied by “open aperture” and “closed aperture” Z-scan techniques. Both compounds showed typical nonlinear absorptions and refractions, and the third-order nonlinear susceptibilities have been found to be very high in all cases. The significant nonlinear optical response, combined with the possibility to further modify it, by changing the π-linking groups and the electron donors or acceptors, suggests that these systems can prove to be important candidates for a variety of photonic/optoelectronic applications.

Synthesis and co-assembly of gold nanoparticles functionalized by a pyrene–thiol derivative

We successfully synthesized a series of gold nanoparticles capped with 11-(4-(pyren-1-yl)phenoxy)undecane-1-thiol (A-SH) and with 1-dodecanethiol. The homodispersed gold nanoparticles were fully verified by TEM, UV-Vis and PL spectroscopy. TEM images of the nanoparticles showed similar particle sizes at approximately 2.5 nm also evidenced by the absorption spectra. By solvent-exchange co-self-assembly of a pyrene derivative composited with these functionalized nanoparticles, the different arrangements of Au nanoparticles were observed. Compared to Au nanoparticles functionalized by 1-dodecanethiol (GNP), the pyrene–thiol-capped gold nanoparticles (GNP-A) showed better dispersity in the pyrene derivative matrix because of their π–π interactions.

Disk-shaped symmetric hexa-substituted triphenylene derivatives: Synthesis, physical properties and self-assembly

A series of triphenylene derivatives with six symmetric substituents was synthesized from hexabromotriphenylene. The synthesis was conducted by six-fold palladium-catalyzed Hagihara-Sonogashira cross- coupling reactions to yield the hexa-alkynyl substituted triphenylene derivatives of HTP1, HTP2, HTP3 and HTP4. The six symmetric substituents can not only endow the triphenylene the longer π-conjugated range, but also increase the solubility of the compounds. Their photophysical, electrochemical, thermal properties were investigated respectively. With the comparison of their properties, the structure-property relationships were established which demonstrated the influences of different substituents on the electronic nature and the mesomorphic phase of these disk-shaped molecules. In addition, with the scanning electron microscopy(SEM) and polarized optical microscopy( POM) characterization, the self-assembly behaviors of the compounds were also investigated.