Keywords: 3-D array, nanostructures, nanocomposites, nanotechnology, thin films, nanorod, nanowire, interfacial tension, thermodynamic stability, aqueous solution, metal oxide nanomaterials
On the design of advanced metal oxide nanomaterials
A novel growth concept and a low-temperature aqueous chemical growth (ACG) thin film processing technique are presented that aim to contribute to the rational fabrication of smart and functional metal oxide particulate thin films and coatings. Such purpose-built materials are modelled, designed, and engineered to match the physical, chemical, and structural requirements of their applications. The concept involves a thermodynamic model monitoring the nucleation, growth, and ageing processes via the chemical and electrostatic control of the interfacial free energy of the system. It enables the control of the size of nano-, meso-, and micro-crystallites, their surface morphology, their orientations onto substrates as well as their crystal structure. The templateless and surfactant-free aqueous synthesis method allows generation, at large-scale, low-cost, and mild temperatures, of advanced metal oxides thin films with designed complexity. It features two- and three-dimensional (patterned) arrays and nanocomposites of transition metal oxides consisting of various isotropic and anisotropic building-blocks with advanced architectures. Such materials are designed to develop a new generation of metal oxide-based composites for optical, optoelectronic, magnetic, and sensor devices.