Tuning Optical and Electrical Properties of Ultra-Fast Prepared Nanoflower Mg:ZnO Films by MWCNTs Coating

Abstract

Mg doped ZnO films were coated multi-walled carbon nanotubes (MWCNTs) via fast chemical bath onto ZnO seed layers. XRD analysis showed preferential orientation shift from high-energy (002) peak to low-energy (101) peak with MWCNTs coating. Average crystalline size of Mg doped ZnO samples are 15 nm. diameter and 50% percent reduction has been observed with MWCNTs coating. SEM images reveals the presence of high accumulative nanoflower forms on Mg:ZnO surfaces and homogenous net-shaped coating has been achieved by MWCNTs inclusion so active surface area may increase. No major difference of optical absorption edge is detected in both films however MWCNTs coating cause an increase direct band gap. Due to Burstein-Moss effect, Mg:ZnO and Mg:ZnO/MWCNTs films with using Tauc plot calculated band gap values are 3.04 eV and 3.34 eV, respectively. From FTIR spectra, no obvious change is not detected the functional groups of the samples. Electrical studies show that MWCNTs decrease the resistance and the resistance of films at room temperature were calculated 29.85 and 8.53 k for Mg:ZnO and Mg:ZnO/MWCNTs films , respectively.