Effect of organic capping agents on the optical and photocatalytic activity of mesoporous TiO2 nanoparticles by sol–gel method

Abstract

In this work, the effect of capping agent effects on the structural, morphological, optical properties and photocatalytic removal of Rhodamine B (RhB) dye has been investigated. TiO 2 nanoparticles were synthesized by a simple, fast and ecofriendly sol-gel method, in the presence of various capping agents, including ethylenediamine, polyvinyl alcohol (PVA), ethylene glycol, glucose and valine. The obtained TiO 2 nanoparticles have been characterized by X-ray diffraction (XRD), energy dispersive X-ray analysis, high resolution scanning electron microscopy and transmission electron microscopy, UV-visible absorption and photoluminescence (PL) spectroscopy. XRD pattern reveals the polycrystalline nature of TiO 2 with anatase structure. The results revealed that the optical absorption band of TiO 2 nanoparticles varied by capping agents. PL spectra exhibited visible emissions due to the formation of defects in the band gap region of TiO 2 nanoparticles. The photocatalytic degradation of RhB dye by synthesized TiO 2 nanoparticles using different capping agents was investigated under UV irradiation and the results demonstrated that TiO 2 nanoparticles have appreciable photocatalytic activity for decomposing RhB dye when PVA was used as a capping agent. The results explained that the preparation of TiO 2 nanoparticles showed a high efficiency in the removal of organic dyes.

Synthesis of TiO2 nanoparticles by chemical and green synthesis methods and their multifaceted properties

“…Among them, TiO 2 NPs are a well-known semiconductor with a wide bandgap of 3.2 eV for anatase and 3.0 eV for rutile phase [9], but the brookite phase is rare to obtain [10]. The Anatase and rutile phase of TiO 2 exhibits a tetragonal crystal structure, but the brookite phase is an orthorhombic structure [11]. The transition metal oxide, mainly TiO 2 , is widely used in cosmetics, photocatalysts, medicines, sensors, and solar cell applications because of its peculiar properties like interconnected pores and large surface area [12].…”

Bis(4-methylpiperidine-1-carbodithioato)-lead(II) and Bis(4-benzylpiperidine-1-carbodithioato)-lead(II) as Precursors for Lead Sulphide Nano Photocatalysts for the Degradation of Rhodamine B

“…It has been shown that reduced agglomeration of nanoparticles increases the accessible surface area on the material, which could lead to an increase in their photocatalytic efficiency [ 36 ]. Other studies have shown that if the surface morphology of nanoparticles is rough, it enhances the photocatalytic degradation efficiency of the material [ 37 , 38 ]. TOPO-PbS1 shows a flaky surface morphology while the TOPO-PbS2 SEM image reveals a closely packed spherical surface morphology.…”

Experimental and computational study of metal oxide nanoparticles for the photocatalytic degradation of organic pollutants: a review

“…45,52 The finally heated and dried have the possibility to give us metal oxide in a form of bulk materials, nanoparticles, or oxygen vacancy based on the heat-treatment process done. 28 A variety of metal oxide nanoparticles such as ZnO, 53 TiO 2 , 54 MgO, 55 ZrO 2 , 56 CuO, 57 and Nb 2 O 5 /SiO 2 (ref. 58) were synthesized by the sol–gel process.…”