Optical Band Gap Estimation of ZnO Nanorods

Abstract

The optical band gap energy of ZnO nanorods was estimated by different methods found in literature. These nanorods were deposited onto TiO 2 covered borosilicate glass substrates by aerosol assisted chemical vapor deposition. Characterization techniques were employed to reveal the crystalline structure, surface morphology and optical properties of the sample. The analysis proved that hexagonal cross-section ZnO nanorods in the wurtzite phase were grown onto a TiO 2 buffer thin film of anatase. Variations in the components of transmittance and reflectance were associated with the development of a rough surface. Such fluctuations were correlated with the equations employed to estimate the optical band gap. The different methods indicated band gap values of 3.17 to 3.24 eV. The energy band gap of 3.24 eV agrees to that reported in the literature for ZnO nanorods. Fluorescence spectroscopy confirmed the accuracy of the mathematical predictions since an emission at 380 nm (3.26 eV) was seen.

Efficient visible light photocatalysis of benzene, toluene, ethylbenzene and xylene (BTEX) in aqueous solutions using supported zinc oxide nanorods

“…The bandgap (Eg) of ZnO was found to be around 3.23 eV obtained by using tauc plot [ 65 ] as shown in Fig 4 (inset). Similar values of bandgap was also reported previously in literature [ 50 , 66 ]. The visible light absorption by ZnO nanostructures have been attributed due to the presence of native point defects in the crystal lattice of ZnO which reduce the energy required for exciton pair generation upon photo-excitation [ 67 , 68 ].…”

Titanate Tubular Loaded Diatom Fabricated by a Facial Hydrothermal Method for Photocatalytic Enhancement under Visible Light Irradiation

“…4a shows the UV-vis diffuse absorption spectra of TNT and D/TNT composite. There are several techniques to derive bandstructure of the semiconductor through this measurement [21][22][23]. One of the simple and useful methods is Tau's plot with Kubelka-Munk (KM) function.…”

Nb-doped Ti2O3 Films Deposited Through Grid-Assisted Magnetron Sputtering on Glass Substrate: Electrical and Optical Analysis

“…In many cases, the effects are small enough to be neglected as the results found in the literature 32,27,35 . This is why tables of transparent optical materials properties generally list only the real parts 32,36 .…”