Abstract
ZnO is one of the most important industrial metal oxide semiconductors. However, in order to fully realise its potential, the electronic structure of ZnO has to be modified to better fit the needs of specific fields. Recent studies demonstrated that reactive magnetron sputtering under Zn-rich conditions promotes the formation of intrinsic ZnO defects and allows the deposition of metallic Zn phase-rich ZnO films. In photocatalytic efficiency tests these films were superior to traditional ZnO oxide, therefore, the purposeful formation of intrinsic ZnO defects, namely Zn interstitials and oxygen vacancies, can be considered as advantageous self-doping. Considering that such self-doped ZnO remains a semiconductor, the natural question is if it is possible to further improve its properties by adding extrinsic dopants. Accordingly, in the current study, the metallic Zn phase-rich ZnO oxide film formation process (reactive magnetron sputtering) was supplemented by simultaneous sputtering of copper or carbon. Effects of the selected dopants on the structure of self-doped ZnO were investigated by X-ray diffractometer, scanning electron microscope, X-ray photoelectron spectroscope and photoluminescence techniques. Meanwhile, its effect on photocatalytic activity was estimated by visible light activated bleaching of Methylene Blue. It was observed that both dopants modify the microstructure of the films, but only carbon has a positive effect on photocatalytic efficiency.
Highlights
Our earlier study demonstrated that reactive magnetron sputtering under Zn-rich conditions promotes the formation of intrinsic ZnO defects and allows the deposition of metallic Zn phase-rich ZnO oxide films
In our previous study we demonstrated that the process of Radio frequency (RF) reactive magnetron sputtering of Zn in an Ar-O2 atmosphere has a tendency to shift towards one of two distinct modes: (i) ZnO oxide phase deposition mode, or (ii) metallic Zn phase deposition mode [35]
The small effect of copper doping was explained by the relatively similar effects caused by the intrinsic ZnO defects and copper dopants
Summary
Zinc oxide is an important industrial material extensively used in numerous products such as rubber, plastic, ceramics, glass, medicine, food, pigments, coatings and others [1,2,3,4,5]. In these products, traditional industries exploit the appealing bulk properties of ZnO, namely, high refractive index [6], high thermal stability and conductivity, coupled with a relatively low thermal expansion [5,7], high UV radiation absorbance [8], deodorising and antibacterial properties [9], etc.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
