Optical properties of ZnO nano fiber thin films grown by spray pyrolysis of zinc acetate precursor

Abstract

Good homogeneous and stoichiometric ZnO nanofiber thin films have been deposited onto cleaned glass substrate by a simple spray pyrolysis technique under atmospheric pressure using zinc acetate precursor at temperature 200 °C. Films of various thicknesses have been obtained by varying the deposition time, while all other deposition parameters such as spray rate, carrier gas pressure and distance between spray nozzle to substrate were kept constant. Surface morphology and optical properties of the as deposited thin films have been studied by Scanning Electron Microscopy (SEM) attached with an EDX and UV visible spectroscopy. From EDX data, atomic weight % of Zinc and Oxygen were found to be 49.22 % and 49.62 % respectively. The SEM micrograph of the film shows uniform deposition and scattered nano fiber around the nucleation centers. The optical band gap of the ZnO thin films was found to be in the range 3.3 to 3.4 eV and the band gap decreases with thickness of the film. Optical constants such as refractive index, extinction coefficient, real and imaginary parts of dielelectric constants were evaluated from reflectance and absorbance spectra.

Characterization and study of antibacterial activity of spray pyrolysed ZnO:Al thin films

“…The decrease in the extinction coefficient value of Aldoped films indicates a better homogeneity at higher Al concentration (Shanmuganathan et al 2013). At much higher Al concentration, the extinction coefficient was further increased which is attributed to the appearance of crystal defects (Islam and Podder 2009).…”

“…The refractive index of Al-doped film shows a variation up to 2.64 in the visible region which is preferred for antireflection coating materials. Low refractive index was observed for higher Al concentration (8 at.%), which is attributed to the presence of impurities and defects (Islam and Podder 2009) Photoluminescence (PL) analysis Figure 9 shows PL spectra of pure and Al-doped ZnO thin films. A strong near-band-edge emission (NBE) was observed for all films.…”

Nanocrystalline transparent SnO2‐ZnO films fabricated at lower substrate temperature using a low‐cost and simplified spray technique

“…Among the available TCOs, tin oxide films are extensively used in opto-electronic devices, due to their low electrical resistivity, high optical transmittance and good chemical stability [3]. Similarly, zinc oxide (ZnO) attracts the attention to the scientific community as a 'future candidate' for device applications [5], as it has several advantages over other TCOs such as In 2 O 3 , Cd 2 SnO 4 and SnO 2 due to the unique combination of desirable properties: stability in hydrogen plasma atmosphere, non-toxicity, good optical, electrical and piezoelectric characteristics, thermal stability, material abundance and most importantly low cost [6][7][8]. Minami et al [9] combined these two materials and obtained a new TCO material, SnO 2 -ZnO, a multicomponent metal oxides system, which has the advantages of ZnO in addition to that of SnO 2 .…”

Optical Properties of Poly (vinyl alcohol) PVA Films Doped With Fe Citrate

“…The complex optical constant (refractive index) of the prepared sampleshas been calculated from the R using the following relation [06,05]. Table (0) can be attributed to the increasing of the backing density as a result of filler content [00].…”