Chapters authored
Metal Oxide Nanowires as Building Blocks for Optoelectronic Devices
Metal oxide nanowires have become the new building blocks for the next generation optoelectronic devices due to their specific features such as quantum confinement and high aspect ratio. Thus, they can be integrated as active components in diodes, field effect transistors, photodetectors, sensors, solar cells and so on. ZnO, a n-type semiconductor with a direct wide band gap (3.3 eV) and CuO, a p-type semiconductor with a narrow band gap (1.2–1.5 eV), are two metal oxides which were recently in the spotlight of the researchers for applications in the optoelectronic devices area. Therefore, in this chapter we focused on ZnO and CuO nanowires, the metal oxides nanowire arrays being prepared by straightforward wet and dry methods. Further, in order to emphasize their intrinsic transport properties, lithographic and thin films deposition techniques were used to integrate single ZnO and CuO nanowires into diodes and field effect transistors.
Part of the book: Nanowires
Bioinspired Fibrous Architectures Based on ZnO Templated by Eggshell Membranes
ZnO-based nanostructures emerge as promising materials due to their potential applications in fields including electronic devices, photodetectors, photocatalysts, biocides, etc. The bio-template-mediated synthesis is a straightforward approach for obtaining inorganic or hybrid organic/inorganic materials with tailored morphologies and functional properties. Eco-friendly waste, eggshell membrane (ESM) is an ideal bio-template for the development of 3D hierarchical porous architectures due to its specific 3D interlaced fiber protein network structure. Therefore, this chapter is focused on the ESM-mediated synthesis of 3D fibrous architectures based on ZnO, the ESM organic network being functionalized with inorganic nanostructures or replicated into an inorganic one as follows: i) coated with ZnO layer by RF magnetron sputtering, (ii) covered with ZnO by electroless deposition and (iii) replicated into ZnO web by biomorphic mineralization. The obtained ZnO shows wurtzite structure, band-gap value and emission bands typical for this semiconductor. The electrical properties of the ZnO fiber webs were measured using interdigitated metallic electrodes patterned substrates. The ESM conversion from a bio-waste into new value-added nanomaterials is very attractive from the sustainability and recycle waste perspective, the ZnO-based fibrous architectures featured by a large specific surface area having potential applications in water purification, photocatalysis or chemical sensors areas.
Part of the book: Zinc Oxide Nanoparticles - Fundamentals and Applications [Working title]