Hierarchical Nanomaterials by Selective Deposition of Noble Metal Nanoparticles: Insight into Control and Growth Processes

Complex hierarchical metamaterials are currently the focus of many cutting-edge studies due to their potential to advance such critically important areas of technology as energy storage and transformation, sensing, photovoltaics, nano-medicine, antibacterial and self-regenerating materials. However, the deterministic design of novel hierarchical metamaterials remains problematic due to the lack of efficient, highly reliable methods for controlling the internal structure and architecture of materials. A comprehensive advanced model is proposed to simulate the formation of complex hierarchical metamaterials with a controllable structure. The control is achieved via selective deposition of noble metal nanoparticles (Au, Au, Pd, Pt). Moreover, the novel method for the nanofabrication is theoretically examined and experimentally verified. This approach allows for the sophisticated spatiotemporal control of growth conditions and, as a result, achieving the targeted internal structure of metamaterials. This opens a way to the deterministic design and formation of complex multi-material metamaterials on the basis of metal oxides and noble metal nanoparticles. Moreover, a fundamental insight related to the longstanding question about the prevalence of bottom-up versus top-down growth for various materials and systemswhich is challenging to directly verify experimentally is presented.