Improving the photocatalytic performance of conducting polymer polythiophene sensitized TiO2 nanoparticles under sunlight irradiation

Abstract

Titanium dioxide (TiO 2 ), polythiophene and polythiophene/TiO 2 were prepared by sol-gel and solid-state reaction methods. Water-free iron(III) chloride (FeCl 3 ) was used as an oxidant. The phase composition, morphology and the spectral properties of the products were characterized by XRD, TEM, UV-Vis and FT-IR techniques. The photocatalytic activity of the products was evaluated by the degradation of methyl orange under sunlight irradiation. TEM results showed that the polythiophene/TiO 2 composite particles were well dispersed, rod-like shaped with 20 9 80 nm dimensions. UV-Vis analysis indicated that the absorption edge of polythiophene/TiO 2 was 605 nm. Compared with the unmodified TiO 2 and bare polythiophene, polythiophene/TiO 2 exhibited largely enhanced activity for the photocatalytic degradation of methyl orange under sunlight irradiation. A degradation efficiency of methyl orange of 85.6% could be obtained within 120 min. The sensitization mechanism of polythiophene for the TiO 2 photocatalyst is discussed briefly.

Photocatalytic reduction of CO 2 into methanol and ethanol over conducting polymers modified Bi 2 WO 6 microspheres under visible light

“…-0.72 and 1.78[48], -1.3 and 0.8[49], as well as -1.5 and 0.45 eV[50], respectively. The CB and valence band (VB, calculated from the equation E VB = E CB + E g ) of Bi 2 WO 6 HHMS are calculated to be ca.…”

“…The larger difference of corresponding relative energy level between conducting polymer and Bi 2 WO 6 (LUMO vs. CB, HOMO vs. VB) can lead to better charge separation and stabilization, which benefits to the improvement of photocatalytic activity. Furthermore, the HOMO-LUMO gaps of PPy, PANI, and PTh are 2.50, 2.10, and 1.95 eV, respectively[48][49][50]. The lower HOMO-LUMO gap means that more photons can be absorbed by CP/Bi 2 WO 6 under visible light irradiation, which favors their visible light photocatalytic activity.…”

Preparation and characterization of polypyrrole/TiO2 nanocomposites by reverse microemulsion polymerization and its photocatalytic activity for the degradation of methyl orange under natural light

“…These conductive polymers possess a relatively narrow band gap and can enable an efficient separation of charge, which is important for photocatalytic application . Therefore, many researchers have focused on the preparation of TiO 2 /conductive polymer composites to overcome the shortcomings of TiO 2 . Among these conductive polymers, polypyrrole (PPy) is appealing because of its high conductivity, good environmental stability, and easy preparation by both chemical and electrochemical methods.…”

A novel lactose biosensor based on electrochemically synthesized 3,4-ethylenedioxythiophene/thiophene (EDOT/Th) copolymer

“…The bands at 1198 and 1180 cm −1 together form a shoulder at 1186 cm −1 in the spectra of copolymer. The bands at 684 and 690 cm −1 are attributed to typical C-S stretching [29]. The bands at 1514 and 1515 cm −1 show the C]C stretching for PEDOT and copolymer, respectively [30].…”