Deactivation of photocatalytically active ZnO nanoparticle by surface capping with poly vinyl pyrrolidone.

Abstract

Nanoparticles of zinc oxide (ZnO) were prepared by the precipitation method from zinc sulphate (ZnSO 4 .7H 2 O) and sodium bicarbonate (NaHCO 3). Organization, stabilization of the ZnO nanoparticles from further growth and partially inhibiting the photodegradation was achieved by capping with poly vinyl pyrrolidone (PVP). Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to investigate the structure, morphology and particle size. Thermogravimetric-differential thermal analysis (TG-DTA) was used to study the thermal behavior. In addition, photocatalytic degradation of Rhodamine B (RhB) in aqueous solution was performed using bare and modified ZnO nanoparticles under the illumination of UV light. Various parameters affecting the degradation performance such as catalyst loading, initial dye concentrations, pH and concentration of capping agent were examined. The results showed that PVP capped ZnO nanoparticles have reduced photocatalytic activity than that of bare ZnO nanoparticles. The reduction in the chemical oxygen demand (COD) and total organic carbon (TOC) results revealed the reduced photocatalytic activity of PVP capped ZnO. The UV-shielding property was evaluated by measuring the transmittance. The reduced photocatalytic activity of PVP capped ZnO nanoparticles will enhance their performance as durable, safe and non reactive UV blockers in cosmetics.

Preparation of poly(N-vinylpyrrolidone)-stabilized ZnO colloid nanoparticles

“…The absorption peak at 1373.6 cm −1 is due to the С–Н bond in PVP [21]. Other important peaks at 1287.6 cm −1 and the doublet at 1437.8 cm −1 , 1422.4 cm −1 are assigned to the C–N stretching vibrations and the attachment of CH 2 groups in the pyrrole ring of PVP [22–23]. A comparison of the spectra of the prepared ZnO/PVP nanoparticles (Fig.…”

Red shift of the band-edge photoluminescence emission and effects of annealing and capping agent on structural and optical properties of ZnO nanoparticles

“…There are various reports of the synthesis of ZnO nanomaterials by using various capping agents and surfactants like polyethylene glycol (PEG), ethylenediaminetetraacetic acid (EDTA), polyvinylpyrrolidone (PVP), triethanolamine (TEA), tetraethylammonium bromide (TEAB), 2-aminothiol, 3-aminopropyl trimethoxysilane, tetraethyl orthosilicate (TEOS), mercaptosuccinic acid, 3-mercaptopropyl trimethoxysilane, oleic acid, aminopropyltriethoxysilane, etc. [20][21][22][23][24][25][26][27][28]. Sudha et al [21] showed that PEG capped ZnO NPs prevents agglomeration and with increasing PEG concentration, various morphologies and sizes of ZnO NPs can be obtained.…”

“…It has been demonstrated that ZnO NPs when capped with 2-aminothiol, EDTA, TEA and TEAB can improve the optoelectronic properties, and particles with various shapes and morphologies have been synthesized with those capping agents [22][23]. In addition to capping agents, use of surfactants during synthesis of ZnO can also change the optical and electronic properties of ZnO NPs [24][25][26][27][28]. R. Hong et al [24] showed the reduction of photocatalytic activities and decrease in agglomeration of the particles using oleic acid as the coating.…”

Development and Evaluation of Polymer-bound Glibenclamide Oral Thin Film

“…A peak at 1643.27 cm -1 was assigned to the stretching vibration of the C=O. Other imperative peaks at 1287.50 cm -1 and the doublet at 1438.03, 1422.04 cm -1 were assigned to the C-N stretching vibrations and the attachment of CH 2 groups in the pyrrole ring of PVP [42,43]. The spectra of optimized GLB thin film (Figure 3c) exhibited all the principle peaks present in the PVP thin film.…”