Dottorato in PROCESSI CHIMICI PER L'INDUSTRIA E PER
L'AMBIENTE

Titolo della tesi: Development and production of Bimetallic Nanomaterials by means of a Spinning disc reactor for Enviromental and industrial applications

This PhD thesis reports about an in-depth study on the synthesis, characterization and the application of bimetallic nanomaterials, focusing on their potential use for environmental remediation and energy conversion. The research emphasizes the development of Fe, Ni and Al bimetallic oxides and Layered Double Hydroxides (LDHs) nanoparticles using advanced synthesis techniques, including Spinning Disc Reactor (SDR) technology and the employment of hydrothermal methods. Together, these techniques allowed to produce nanomaterials with a precisely controlled sizes, shape and surface properties, which are crucial for catalytic performance optimization. A significant part of the research involves the integration of these kind of bimetallic oxides with graphitic carbon nitride (g-C₃N₄) leading to composite catalysts. The adopted hybrid approach aims to enhance the photocatalytic properties of the material, in particular for the degradation of persistent organic pollutants in water and for energy conversion processes such as solar-driven hydrogen production. The obtained composites demonstrated a superior light absorption and charge separation efficiency, leading to enhanced photocatalytic activities compared to conventional materials. Furthermore, the thesis explores the doping of these bimetallic oxides with noble metals such as silver (Ag). Noble metal doping was found to significantly improve the catalytic activity, particularly in photocatalytic and electrochemical applications, such as the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR). The presence of noble metals promotes electron transfer and introduced additional active sites, thereby improving the overall efficiency of these catalytic processes. Comprehensive characterization of the synthesized nanomaterials was performed using a range of different techniques, including transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and electrochemical analyses. These characterizations confirmed the structural integrity and enhanced properties of the nanomaterials, underpinning their high catalytic performances. The research was able to demonstrate that these bimetallic nanomaterials qualifies for practical applications in the field of environmental remediation, such as water purification, and in energy technologies, including water splitting and hydrogen production. Moreover, the findings was developed with insight to a potential scaling up of the proposed synthesis methods for industrial applications and suggest more future research directions, in exploring new metal combinations and green synthesis techniques to further enhance the environmental sustainability and performance of these nanomaterials.