Effect of Plasma-Activated Zinc Oxide Surface on Liquid Stability

Abstract

The ZnO is an essential material in material science, agriculture, food industry, cosmetics, medicine etc. Most applications exploit ZnO physicochemical properties such as optical, electrical, mechanical and thermal. In material science, ZnO is commonly used in gas sensors, light-emitting diodes, field-effect transistors, UV lasers, photodetectors, solar cells, photo and heterogeneous catalysis. The ZnO characteristics for different applications can be controlled by size and morphology of particles with numerous techniques.In this work, we study the effect of UV light and plasma treatment on ZnO surface morphology, crystallography and effect on its other intrinsic properties. For study, the UV-A/C light is used and compared to atmospheric pressure plasma generated in Ar or He as well as low-pressure RF – ICP plasma generated in oxygen gas. The research is focused on how UV or other plasma related changes influence the material intrinsic properties and change stability of liquid organic compounds in low ppm concentrations. The resulting interaction between stable liquid and modified material namely result in creation of other unstable molecules and compounds as well as reactive species. This approach enables improved design of catalytic performance of nanomaterials by designing their surface properties by plasma, beyond mere enhancement of surface area. The targeted liquids for modifications are thiophens in organic solvents, where we need to look at interactions of this liquids with material. To unravel these interactions, various analyses are used including UV-Vis, HPLC, and NMR. Further for surface characterisation of materials, the analyses including XPS, FTIR, UV-Vis, BET, SEM and TEM are used. The obtained results give then systematic explanation, how UV or plasma changes of material intrinsic properties translate into targeted liquid interactions and modifications.