SYNTHESIS, CHARACTERIZATION AND EVALUATION OF Ag-TiO2 NANOCOMPOSITES FOR PHOTO-CATALYTIC DEGRADATIONOF SELECTED CHLOROPHENOLS

Digest Journal of Nanomaterials and Biostructures

K. Kotlhao¹ 

关键词: Nanoparticles;    Characterization;    Ag - TiO2;    Photocatalytic degradation;   

DOI  :  

学科分类：生物技术

来源: Institute of Materials Physics

【 摘 要 】

Anatase TiO2 and Ag nanoparticles were synthesized using reduction and precipitation method respectively. The prepared nanoparticles and nanocomposites were characterized using ultraviolet visible spectroscopy (UV-Vis) photoluminescence (PL), X-ray diffractometry (XRD), scanning transmission electron spectroscopy (STEM) and Energy Dispersive X-ray (EDX). The prepared nanoparticles (Ag, TiO2) and nanocomposites (Ag-TiO2: 1, 3, 5 %) were investigated for their photocatalytic properties on 2-chlorophenol, 2,4- dichlorophenol and 2,4,6-trichlorophenol using UV light for irradiation. The UV results showed band gap reduction from 3.38 (TiO2), 3.36 (Ag-TiO2 1 %), 3.32 (Ag-TiO2 3 %) to 2.99 (Ag-TiO2 5%). The UV-Vis spectrum for pure silver showed a slightly broad absorbance peak in the range 384 - 410 nm which is characteristic of surface plasmon resonance for silver. The XRD pattern obtained corresponded to the anatase phase according to JCPDS card no. 21-1272. The estimated crystallite sizes ranged from 9.40 nm, 12.41 and 11.44 nm for Ag-TiO2 (1 %) Ag-TiO2 (3 %) and Ag-TiO2 (5 %) respectively. The STEM images did not show the expected trend in size, however, the presence of silver appeared as bright white irregular shaped spots. The mean particle size ranged from about 6.78 ±1.44 nm, 10.64 ± 1.91 nm, and 8.54 ± 2.01 for Ag-TiO2 (1 %) Ag-TiO2 (3 %) and Ag-TiO2 (5 %) respectively. Photocatalytic degradation showed better performance with Ag- TiO2 at initial concentration of 5 ppm and pH 11 compared to bare Ag and TiO2.

【 授权许可】

Unknown