Self-Supported Monolith Formation of Silica Nanoparticles with Hollow Nickel Core

Along with a specific size (1-100 nm), nanoparticles are characterized by high specific surface area and surface energy. Due to these advantages, nanoparticles have drawn attention and shown potential in various fields, such as catalysis, optics and medicine. However, “naked” nanoparticles suffer from significant shortfall, in particular its limited stability. In addition, commonly used nanoparticles are in the form of powder and will raise health and environmental concerns. Core-shell-nanoparticle (CSN) could help to overcome the limited stability of naked nanoparticles by mitigating particle agglomeration, while assembly of nanoparticles into macroscopic structures, either via self-assembly or guided assembly, could address the health and environmental concerns. Our work investigated the guided self-assembly of hollow Ni@SiO2 CSNs into macroscopic monoliths with dimensions in the centimeter range. By chemically cross-linking these nanoparticles and carefully controlling the cross-linking reaction, we were able to synthesize, for the first time, structurally stable, self-supporting monolithic structures composed solely of CSNs. Critical synthesis parameters, including temperature, pH, and reactant concentrations were identified and will be discussed in my presentation.