Preparation of Titanium Dioxide Nanoparticles Immobilized on Polyacrylonitrile Nanofibres for the Photodegradation of Methyl Orange

Abstract

Herein, we describe the synthesis of titanium dioxide (TiO2) nanoparticles by the hydrolysis and condensation of titanium tetrachloride. The resulting nanoparticles were immobilized on polyacrylonitrile (PAN) based nanofibres by an electrospinning technique in order to allow simple isolation and reuse of titania semiconductor photocatalyst. The composite nanofibres were heat treated to convert the polymer nanofibres to carbon nanofibres and to convert amorphous TiO2to crystalline TiO2. X-ray diffraction (XRD) analysis showed that the rutile phase was the major phase and the equatorial peaks of PAN disappeared after heat treatment at 600°C. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analysis confirmed that some TiO2nanoparticles were encapsulated whereas some were surface residing on the electrospun nanofibres. The TiO2nanoparticles were found to lower the cyclization temperature of PAN as indicated by differential scanning colorimetry (DSC) and differential thermal analysis (DTA). Photocatalytic studies on the degradation of methyl orange dye under UV light irradiation showed that composite nanofibres were capable of degrading organic contaminants in water. The carbon nanofibres with surface residing titanium dioxide nanoparticles (TiO2/CNF-SR) showed the highest photocatalytic activity (59.35% after 210 minutes) due to direct contact between the TiO2photocatalyst and methyl orange.

Plasticizer effect on dielectric properties of poly(methyl methacrylate)/titanium dioxide composites

“…[11][12][13][14][15][16][17] Although anatase, rutile and brookite phases are available for TiO 2 , anatase form which is metastable in a wide temperature range is the most used TiO 2 types (antase phase is thermally unstable and turns into rutile phase above 600 � C). 11,12,18 Organic-inorganic composite dielectric materials provide many advantages with their mechanical and electrical properties. Polymer composites are mostly produced by mixing, blending, crosslinking polymeric materials and inorganic additives.…”

“…11-17 Although anatase, rutile and brookite phases are available for TiO 2 , anatase form which is metastable in a wide temperature range is the most used TiO 2 types (antase phase is thermally unstable and turns into rutile phase above 600°C). 11,12,18…”

Optimized Loading of TiO2 Nanoparticles into Electrospun Polyacrylonitrile and Cellulose Acetate Polymer Fibers

“…Lower concentration loadings of TiO 2 nanoparticles onto CA were used as compared to the concentration loading of PAN; this is due to the interaction of the nanoparticles with the polymer solution. It was observed that when adding more concentration of TiO 2 nanoparticles onto CA, the solution became more concentrated which hindered the formation of the nanofibers due to the high viscosity, making it difficult to control the flowrate of the polymer solution through the capillary [11,14]. It is observed that the fiber diameter of pure CA is 338 nm whereas the addition of 0.2 and 0.4 wt % nanoparticles improved fiber morphology with a decreased average diameter of 192 and 250 nm, respectively.…”

“…Electrospinning setup consists of three primary components: a high voltage power supply, a syringe with metallic needle, and a grounded collector [10]. In the usual electrospinning process, a high voltage is applied on the polymer solution, which causes electrostatic charging of the droplet of the polymer [11]. A charged jet of polymer solution is ejected from the tip of the needle when the applied electric field overcomes the surface tension of the polymer droplets [12].…”

Polyacrylamide exotemplate-assisted synthesis of hierarchically porous nanostructured TiO2macrobeads for efficient photodegradation of organic dyes and microbes

“…However, the photocatalytic activity of TiO 2 was observed to be affected by the adsorptive nature of the support, 17 and the possible reduction in the available surface-tovolume ratio.…”