Effect of Polymers (PEG and PVP) on Sol‐Gel Synthesis of Microsized Zinc Oxide

Abstract

Fibers irregular and seed-like microcrystalline ZnO were synthesized by using a cost-effective and low temperature aqueous sol-gel method. Various polymers, namely, polyethylene glycol 6000 (PEG 6000) and polyvinyl pyrrolidone (PVP), were used as structure directing agents. The samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The X-ray diffraction pattern revealed the formation of phase-pure ZnO micropowders. It is observed that the polymers play an important role in modifying the surface morphology and the size of the crystallites. A compact granular morphology is observed for the ZnO samples without polymer. The samples exhibit microparticles of size 100 nm for PVP and for PEG-mediated growth, whereas microporous corrugated morphology is observed for added PEG-mediated micropowder. FTIR study is used to confirm the structural modifications occurring in the polymers.

Synthesis of supported silver nano-spheres on zinc oxide nanorods for visible light photocatalytic applications

“…In the lower frequency range (890-1630 cm À1 ) several small absorption peaks were observed, which could be attributed to the different residual groups and reaction byproducts. The absorption peaks at 1630 and 1380 cm À1 represent the asymmetric and symmetric stretching of acetate species [40,41], whereas peak at 1545 cm À1 represents C¼O stretching mode [42]. A small peak observed at 890 cm À1 can be attributed to the C-H out of plane bending from an alkene group [42].…”

“…The absorption peaks at 1630 and 1380 cm À1 represent the asymmetric and symmetric stretching of acetate species [40,41], whereas peak at 1545 cm À1 represents C¼O stretching mode [42]. A small peak observed at 890 cm À1 can be attributed to the C-H out of plane bending from an alkene group [42]. The absorption peak located at 425 cm À1 was assigned to the characteristic stretching mode of Zn-O bond [42][43][44][45].…”

Effect of capping agents: Structural, optical and biological properties of ZnO nanoparticles

“…indicated that ZnO nanoparticles are well crystallized [30][31][32]. Later on, the crystallite size of ZnO nanoparticles were calculated from the peak broadening of diffraction peaks using Scherrer formula [33].…”

“…Symmetric C=O stretching of at 1620 cm -1 and C ̶ H out of plane bending group at 1116 cm -1 are observed[32].…”

Enhancing luminescence of ZnO quantum dots by PEG and oleic acid via a sol–gel method

“…Polyethylene glycol (PEG) could also modify the QDs and control the size of ZnO nanopowders effectively [20,21], which would both adjust the emission spectra and improve the emission intensity of the QDs [22]. PEG would protect the organic packaging materials through reducing the photocatalytic activity of ZnO as well [23].…”