Photocatalytic activity of polyaniline-TiO2 nanocomposites

Abstract

The characteristics of the UV illumination-assisted degradation of Malachite green (MG) on highly active nanostructured-anatase TiO 2 , bulk Polyaniline (PAni), PAni nanoparticles and PAni-TiO 2 nanocomposites have been studied. Dodecylbenzene sulphonic acid doped PAni-TiO 2 nanocomposites were synthesized by a water-assisted self-assembly method. Samples were characterized using transmission electron microscopy, X-ray diffraction studies, Fourier Transform Infra red spectroscopy and photoluminescence studies. Photoluminescence intensity of TiO 2 nanoparticles was found to decrease with the increase of PAni in the nanocomposite which can be attributed to the reduction of electron-hole pair recombination at the interface of PAni and TiO 2 due to electron transfer from TiO 2 to PAni. Exposure to UV light brought about the photocatalytic oxidation of MG in contact with bulk PAni, PAni and TiO 2 nanoparticles, and PAni-TiO 2 nanocomposites. The decrease in absorbance was measured, and its kinetics was analyzed using the Langmuir-Hinshelwood kinetic model. PAni-TiO 2 nanocomposites exhibit higher photocatalytic activity than pure TiO 2 nanoparticles, bulk PAni and PAni nanoparticles under the same degradation condition for MG. The enhanced photocatalytic activity of nanocomposites is attributed to the electron transfer from TiO 2 to PAni resulting in enhancing the oxidative property of the TiO 2 nanoparticles.

Photocatalytic activities of polyaniline-modified TiO2 and ZnO under visible light: an experimental and modeling study

“…The FT-IR spectrum obtained for synthesized PANI was in good agreement with the previous results (Razak et al 2014;Zhang et al 2006;Sarmah and Kumar 2011). The incorporation of TiO 2 nanoparticles caused differences in the peaks of PANI.…”

“…The experimental results obtained in this study are in agreement with previous reports on the photocatalytic reactions of PANI/TiO 2 and PANI/ZnO (Salem et al 2009;Sarmah and Kumar 2011;Eskizeybek et al 2012;Olad and Nosrati 2012). The schematic of the mechanism of photocatalytic degradation of dye using polymeric nanocomposites is presented Fig.…”

“…Among the number of tested photocatalyst materials, TiO 2 and ZnO have been found to provide the best activity and stability in a variety of photocatalytic reactions as they have wide band gap (Eg [ 3.2 eV). Titanium dioxide is the widely preferred as it is non-toxic, stable, biologically inert, and has good absorption/desorption rates (Sarmah and Kumar 2011;Eskizeybek et al 2012). However, TiO 2 is found to be uneconomic in large-scale water treatment applications.…”

Comparative Photocatalytic Degradation of Rose Bengal Dye under Visible Light by TiO2, TiO2/PAni and TiO2/PAni/GO Nanocomposites

“…Additionally, harnessing sunlight can be achieved by the scientists recently, most of the researchers have used conducting polymers to modify TiO 2 to improve visible light photoactivity and electron transfer performance; e.g., Polyaniline/TiO 2 [11], polypyrrole/ TiO 2 [12] and polythiophene/TiO 2 [13]. Many published reports focussed on the preparation and photocatalytic studies on nanocomposites consisting of polyaniline and TiO 2 (PAni/TiO 2 ) [14][15][16][17]. Among these, PAni has several advantageous features over others because of its good environmental stability, ease of synthesis, controllable doping/dedoping chemistry, and reversible electrical properties by controlled charge transfer processes [18,19].The incorporation of inorganic nanomaterials into PAni, thereby forming nanocomposite materials, appears to be an effective approach for preparing photocatalytic materials [20].…”

Study of structural and optical properties of chemically synthesized nanostructured cadmium zinc sulphide films for band gap tunability

“…Nanostructured semiconductors of group II-VI are important materials because of their potential applications in various fields such as in gas sensors, imaging, solar cells, photoconductors, biological detection, UV sensors, short-wavelength laser diodes and various luminescence devices [1][2][3]. Nanostructured CdS and ZnS films are extensively used in various optoelectronic devices and photoconducting cells [4,5].…”