Gold Nanoparticles Decoration of Zinc Oxide Nanostructures for Bio-Sensing Applications

Abstract

ZnO nanowalls (NWLs) is a non-toxic, high surface-to-volume ratio semiconducting nanostructure which has already showed potential applications in biosensing applicationsRecently, it was discovered that decorating the metal oxide nanostructures with noble metal nanoparticles (NP) opens the doors to fabricating biosensors to detect volatile organic compounds. The aim our work is to improve the knowledge and understanding of fabricating ZnO nanowalls decorated with metal nanoparticles.ZnO nanowalls wereas deposited both on rigid on flexible substrates at low temperature using rather simple and low-cost processes.We examined the formation process of ZnO nanowalls on Polyimide substrate and studied the new obtained structure at the nanoscale, at different conditions such as growth temperature, concentration and time. The morphology of the ZnO nanowalls obtained under each of these conditions was studied. The crystal structure of the ZnO nanowalls at different growth temperatures was studied by X-ray diffraction.Next, NP decoration of gold and platinum was conducted. A study of the nucleation and growth of the ZnO nanowalls, and of the NP decoration at different schemes of surface functionalization, was conducted.The first attempts for NP deposition achieved NP clusters with irregular morphology, however at well-kept conditions we succeeded in achieving a good dispersion of NP (figure 1(b).)The metal nanoparticle surface functionalization poses some material-related questions regarding the behavior of that nano-structured material, when exposed to volatile organic compounds (e.g. Ethylene). This will allow us to develop a novel family of biosensors that enable sensitivity, rapidity, and selectivity for the detection of a wide range of target analytes.The final goal is a flexible all-in-one, highly sensitive and selective biosensors using relatively simple and low cost materials and processing. The sensors will use recent advances in functionalized Gold NP decorated ZnO electrodes based sensors. Figure 1