Entity

Time filter

Source Type


Xu C.,Liaocheng University | Zhao J.,Liaocheng University | Wang M.,Central Laboratory of Liaocheng Hospital | Wang Z.,Central Laboratory of Liaocheng Hospital | And 3 more authors.
Electrochimica Acta | Year: 2012

1,3-Bis(9H-carbazol-9-yl)benzene monomer (BCB) is successfully synthesized. Poly(1,3-bis(9H-carbazol-9-yl)benzene) (PBCB) is electrochemically synthesized and characterized. The PBCB shows high outstanding optical contrast (60.98%) and reasonable transparency, with color changes from desirable transparent colorless to yellowish green, and then to green color upon the application of potentials ranging from 0 to 1.25 V. The color switching time and bleaching time of the PBCB film are 2.07 s and 0.45 s at 427 nm. Electrochromic device (ECD) based on PBCB and poly(3,4-ethylenedioxythiophene) (PEDOT) is also constructed and characterized. PBCB/PEDOT device shows a maximum contrast (ΔT %) of 26.64% at 427 nm with response time of 0.90 s and of 43.67% at 625 nm with response time of 0.66 s, respectively. Particularly, the device exhibits transmissive blue at neutral state, good optical memory ability and remarkable stability after 1000 cycles. These properties make the polymer a suitable material for electrochromic applications. © 2012 Elsevier Ltd. All rights reserved.


Xu C.,Liaocheng University | Zhao J.,Liaocheng University | Cui C.,Liaocheng University | Cui C.,Central Laboratory of Liaocheng Hospital | And 3 more authors.
Journal of Electroanalytical Chemistry | Year: 2012

A star-shaped monomer tris[4-(3,4-ethylenedioxythiophene)phenyl]amine (TEPA) was successfully synthesized and electrochemically polymerized to obtain a multielectrochromic polymer (PTEPA). The electroactive yellowish green color film converted to green, blue and steel blue in turn upon applied stepwise oxidations from -0.4 to 0.95 V. The UV-vis spectra showed that the dedoped polymer film has two absorption bands located at 448 and 686 nm, respectively, and the optical band gap was calculated to be 1.3 eV. Maximum contrast (ΔT%) and response time of the PTEPA film were measured as 26.84% and 0.94 s at 448 nm, 17.03% and 1.11 s at 686 nm, respectively. An electrochromic device (ECD) based on PTEPA and poly(3,4-ethylenedioxythiophene) (PEDOT) was also constructed and characterized. This ECD was found to have a neutral green state, good switching times, reasonable contrast, satisfactory optical memories and redox stability. © 2012 Elsevier B.V. All rights reserved.


Wang B.,Liaocheng University | Zhao J.,Liaocheng University | Cui C.,Liaocheng University | Wang M.,Central Laboratory of Liaocheng Hospital | And 2 more authors.
Optical Materials | Year: 2012

Electrochemical copolymerization of 1,4-bis(2-thienyl)naphthalene (BTN) with pyrene is carried out in acetonitrile (ACN) solution containing sodium perchlorate (NaClO 4) as a supporting electrolyte. Characterizations of the resulting copolymer P(BTN-co-pyrene) are performed by cyclic voltammetry (CV), UV-vis spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The P(BTN-co-pyrene) film has distinct electrochromic properties and exhibits three different colors (yellowish green, green and blue) under various potentials. Maximum contrast (ΔT%) and response time of the copolymer film are measured as 37.8% and 1.71 s at 687 nm. An electrochromic device (ECD) based on P(BTN-co-pyrene) and poly(3,4-ethylenedioxythiophene) (PEDOT) is constructed and characterized. Neutral state of device shows green color while oxidized state reveals blue color. This ECD shows a maximum optical contrast (ΔT%) of 24.4% with a response time of 0.43 s at 635 nm. The coloration efficiency (CE) of the device is calculated to be 349 cm 2 C -1 at 635 nm. In addition, the ECD also has satisfactory optical memories and redox stability. © 2012 Elsevier B.V. All rights reserved.

Discover hidden collaborations