Lei Zhang

Publications (2)3.06 Total impact

• Article: Conjugated opto/electroactive ethynylene-carbazole polymers with TTF as pendant group

  Xue-Chao Zhang, Cheng-Yun Wang, Guo-Qiao Lai, Lei Zhang, Yong-Jia Shen
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  ABSTRACT: Three conjugated ethynylene-carbazole polymers with Tetrathiafulvalene (TTF) as pendant group (P1–P3) were synthesized by using sonogashira coupling reaction and characterized by 1H NMR, GPC, CV, UV–Vis, FL, and TGA. CV and UV–Vis spectra showed that an intramoleular interaction existed between the electron-rich moiety TTF and electron-deficient moiety polyethynylcarbazole of the polymers. A strong fluorescence quench (ca. 99%) could be observed, compared to the polyethynylene-carbazole without TTF units, which could be ascribed to the photo-induced electron transfer (PET) interaction from TTF moiety to the polyethynylene-carbazole backbone. The observed onset decomposition temperatures (T d) for P1–P3 varied from 256 to 298°C. The polymers mentioned above exhibited good thermal properties and higher conductivity (neutral conductivity ~7–11×10−7Scm−1; doped conductivity ~6–11×10−4Scm−1). KeywordsCarbazole–TTF–Charge transfer–Electroactive polymer
  Polymer Bulletin 04/2012; 66(7):893-903. · 1.53 Impact Factor
• Article: Fluorene oligomer with tetrathiafulvalenes as pendant groups: synthesis, electrochemical and spectroscopic properties

  Xue-Chao Zhang, Yu Zhang, Cheng-Yun Wang, Guo-Qiao Lai, Lei Zhang, Yong-Jia Shen
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  ABSTRACT: An oligomeric fluorene with pendant TTF units (OFT) was synthesized by the Yamamoto coupling reaction using Ni(COD)2 as catalyst. The fluorescence spectra of fluorene-TTF (3a) and OFT displayed weak fluorescence intensity because of the photoinduced electron transfer (PET) interaction and energy transfer between the TTF and fluorene, while the fluorescence intensity would enhance significantly after chemical oxidation. The absorption spectra and cyclic voltammetry (CV) showed that an intramolecular interaction existed between the TTF and fluorene moieties in OFT, while in 3a such interaction could not be observed, due to the chain propagation of the fluorene backbone and an enhanced internal charge transfer interaction between the two electroactive moieties. Moreover, the conductivity showed that the doped OFT possessed a higher conductivity (1.4×10−3Scm−1) than the doped 3a (9.8×10−5Scm−1). These results demonstrated that OFT was a good candidate of fluorescence switches and conducting materials.
  Polymer Bulletin 04/2012; 63(6):815-827. · 1.53 Impact Factor