Synthesis of Gd2O3 Nanoparticles and Their Photocatalytic Activity for Degradation of Azo Dyes

Abstract

Gadolinium oxide (Gd2O3) nanoparticles were prepared via the reaction of gadolinium nitrate hexahydrate (Gd (NO3)3·6H2O) and ethylamine (C2H5NH2), and their surface morphology, particle size, and properties were examined by using scanning electron microscopy, X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and ultraviolet visible (UV-vis) spectroscopy. The Gd2O3 nanoparticles were used as the photocatalyst for the degradation of various azo dyes, such as methyl orange (MO), acid orange 7 (AO7), and acid yellow 23 (AY23) under irradiation with UV light. The effect of the experimental parameters (initial concentration of azo dyes, dosage of catalyst, and wavelength of UV light) on the photocatalytic properties of the Gd2O3 nanoparticles were investigated. At a constant H2O2 concentration, the photocatalytic degradation efficiency of the Gd2O3 nanoparticles for various azo dyes was in the order: methyl orange > acid orange 7 > acid yellow 23. The kinetics study showed that the photocatalytic degradation of azo dyes was followed by a pseudo first-order reaction rate law.

Ultrasound Assisted Synthesis of Gadolinium Oxide-Zeolitic Imidazolate Framework-8 Nanocomposites and Their Optimization for Photocatalytic Degradation of Methyl Orange Using Response Surface Methodology

“…The Raman spectroscopy results of hybrid Gd 2 O 3 -ZIF-8 nanocomposites show the prominent mode of Gd 2 O 3 and major peaks of ZIF-8 in Figure 2 and the Raman shift ranges from 200 cm −1 to 3500 cm −1 . A peak corresponding to the F g + A g mode of the Gd 2 O 3 nanowires was observed at 358.41 cm −1 [22,26]. The Raman spectroscopy results of hybrid Gd2O3-ZIF-8 nanocomposites show prominent mode of Gd2O3 and major peaks of ZIF-8 in Figure 2 and the Raman shift ran from 200 cm −1 to 3500 cm −1 .…”

“…The Raman spectroscopy results of hybrid Gd2O3-ZIF-8 nanocomposites show prominent mode of Gd2O3 and major peaks of ZIF-8 in Figure 2 and the Raman shift ran from 200 cm −1 to 3500 cm −1 . A peak corresponding to the Fg + Ag mode of the Gd2O3 n owires was observed at 358.41 cm −1 [22,26].…”

“…112), (022), (013), (222), and (114) planes of the sodalite structure (JCPDS 00-062-1030) [23,24]. The crystallite size of the Gd 2 O 3 nanowires in the synthesized Gd 2 O 3 -ZIF-8 nanocomposites was calculated using the Scherrer formula [25,26].…”

Novel Gd2O3/SrFe12O19@Schiff base chitosan (Gd/SrFe@SBCs) nanocomposite as a novel magnetic sorbent for the removal of Pb(II) and Cd(II) ions from aqueous solution

“…[7] Two peaks were observed at 1,472 and 1,073 cm À1 assigned to the stretching vibration of C-O-C and C-N groups, respectively, [7,8] Finally, three weak peaks were observed at 611, 564, and 464 cm À1 to predict the Fe-O, Sr-O, and Gd-O vibration. [6,8,[41][42][43][44][45][46][52][53][54] Figure 2 shows the XRD patterns of Gd/SrFe and its Gd/SrFe@SBCs nanocomposite for Gd/SrFe@SBCs, the XRD peaks observed at 2θ value of 20.73 correspond to the pure chitosan and a shoulder peak at 2θ value of 15 correspond to the Schiff base chitosan. [6][7][8]27,28] In addition, the peaks at 2θ value of 28.87, 32.95, 47.17, and 57.02 correspond to the (222), (400), (440), and (622) planes of the cubic phase of Gd 2 O 3 [52][53][54] and those at [41][42][43][44][45][46] The average crystallite sizes of Gd 2 O 3 and SrFe 12 O 19 in Gd/SrFe were calculated at about 51 and 36 nm, respectively, using Scherrer equation, d = 0.94λ/β cosθ, where d is the crystalline size (nm), λ is the wavelength of the X-ray radiation (1.54 Å), β is FWHM, and θ is Bragg's angle.…”

“…[45][46][47][48][49][50][51] Gd 2 O 3 nanoparticles are chemically and thermally stable, n-type semiconductor, and high dielectric constant has received much attention in various applications. [52][53][54] Until now, many magnetic chitosan nanocomposites have been developed for the removal of heavy metal ions such as Zn(II), Hg(II), Cr(III), Cr(VI), Cu(II), Cd(II), Co(II), and Pb(II). [11,16,18,20,[55][56][57][58][59][60] But, until this moment, a report on the synthesis of Schiff base chitosan nanocomposites using strontium hexaferrite and gadolinium oxide has not been carried out.…”