Morphological, Structural, and Optical Bandgap Characterization of Extracted ZnO Nanoparticles from Commercial Paste

Abstract

ZnO nanoparticles (NPs) were extracted from a commercial paste in both colloidal and precipitate forms. The Zetasizer analysis performed on the colloid showed ZnO NPs ranging from ∼30 nm to ∼100 nm. Thin films of ZnO were deposited on glass substrates by spin-coating technique from a mixture of the extracted colloid and precipitate. The scanning electron microscope (SEM) images showed uniformly arranged, mesoporous, and nanostructured ZnO particles of different shapes, with an estimated film thickness of 0.67 μm. Analysis by energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction analysis (XRD) confirmed the presence of ZnO in the films, with no impurities or remnants of other materials. The XRD analysis showed a polycrystalline nature of the films and identified a pure phase formation of the hexagonal wurtzite structure. The average crystallite size calculated from the diffraction peaks is ∼43.25 nm. The calculated crystal tensile strain is 1.954 × 10−3, which increases the crystal volume by 0.728% compared with the crystal volume of standard ZnO. The calculated crystal parameters are a = b = 3.258 Å and c = 5.217 Å. The calculated dislocation density (d) and bond length Zn–O (L) are 5.35 × 10−4 nm−2 and 2.695 Å, respectively. Ultraviolet-visible absorption spectra showed an optical band gap of ∼3.80 eV.

Structural Properties of Mn Doped ZnO Nanocrystallites Using Wet Chemical Synthesis

“…However, this irregular trend of the values of the lattice parameters found to be increasing and decreasing as doping concentration increases is similar to preceding reports by Babar [9], Lv et al [11], Abdou and Al-mokhtar [14] and Senol et al [33]. The values of the lattice parameters (a and c and their ration c/a) obtained for this work has been supported by the report of Belkhaoui et al [16], Nabil et al [20]) and Ara´ujo J´unior et al [34]. In an ideal wurtzite structure, the c/a ratio is given 1.633.…”

“…The Debye-Scherrer equation ( 7) was used to calculate the average crystallite size, D in nm, [14][15] were as equations ( 8) and ( 9) were used to calculate the dislocation density (δ) [20][21] and the Lattice strain, ε, [21][22] respectively:…”

Highly ordered structure and susceptibility to light absorption of ZnO/calcium phosphate (5%) to enhance the stability of charge diffusion as a methylene blue bond breaker

“…It was found that ZnO is strongly influenced by the treatments given such as thermal, solgel, hydrothermal, and PH. Based on those publications that thermal treatment has a crystallite size tendency in the range of 30-40 nm [49,50], sol-gel ∼20 nm [51], and PH effect ∼50 nm [51]. We suspect that this change in crystal size is strongly influenced by the setting of lattice parameters [52].…”

Solution Combustion Synthesis of Pencil-Shaped ZnO Nanostructures and the Analysis of Their Photocatalytic Properties

“…To understand the crystallographic irregularity within the crystal structure, the dislocation density is calculated for all the samples. 31 The dislocation density is the length of dislocation per unit volume in the crystal and it is in ascending order with the pH of the precursor solutions (Table I). This observation suggest that crystalline lattice is modified along with the morphological variation of the as obtained ZnO samples with the incorporation of defects in the crystals.…”