Structure–property correlation of pure and Sn-doped ZnO nanocrystalline materials prepared by co-precipitation

Abstract

The structural, optical and electrical properties of pure and tin (Sn) doped zinc oxide (ZnO) nanocrystalline materials prepared by co-precipitation method have been studied as a function of Sn doping concentration. The phase identification through powder X-ray diffraction methods confirmed that pure and Sn-doped zinc oxide powder have typical hexagonal wurtzite structure (a ¼ 3.407 A and c ¼ 4.592 A ) with slight change in lattice parameters. The surface morphological examination with field emission scanning electron microscopy revealed the fact that the grains are closely and densely packed and pores/voids between the grains decrease with increasing the doping concentration of Sn from 0% to 15%. The energy bandgap of pure ZnO was found to be 3.35 eV from optical absorption spectra obtained by ultraviolet-visible (UV-Vis) absorption spectrophotometer. The variation of energy bandgap and electrical resistivity of Sn-doped ZnO were also determined with tin doping. Upon increasing the Sn dopant concentration from 0 to 15 wt%, the optical bandgaps of ZnO increases from 3.35 to 3.42 eV. The electrical resistivity of Sn-doped ZnO has been decreased at least two orders of magnitude, i.e. from 1263.17 to 28.64 V cm. This decrement in electrical resistivity may be due to the partial substitution of divalent Zn 2þ ions with tetravalent Sn 4þ ions, generating more free electrons for conduction.

Effect of thickness and reaction media on properties of ZnO thin films by SILAR

“…The bandgap energy values slightly increase with the ZnO thin film thickness in both cases. The increment of bandgap energy is explained that during the growth of ZnO nanostructures lattice deformation of the film decreases 59 . Besides, electrons in the metal oxide semiconductor experience the periodic potential of the ZnO crystal lattice.…”

The Effects of Mn Doping on the Structural and Optical Properties of ZnO

“…where D is a grain size, K is the constant, considered to be 0.9, λ is the wavelength of used X-ray (λ = 1.5406 Å), β is the full width at half maximum (FWHM), and θ corresponds to the intense (002) peak position [42,43].…”

Low Concentration NO Gas Detection Of SnO2 And Zn0.50Sn0.50O Sensors

“…The films with compositions in the range of 0< x <1 have both hexagonal wurtzite and tetragonal crystal phases. The crystal quality of the thin films deteriorated with increasing Sn concentration [18]. This degradation may be connected to the changing in the atomic environment due to the external doping (Sn) of ZnO thin film.…”