Fluorescent Metal Nanoclusters: Synthetic Strategies via Top-down and Bottom-up Approaches

Metal nanoclusters (MNCs) comprised of various metal atoms, exhibit distinct characteristics such as discrete electronic structures, adjustable fluorescence, and remarkable catalytic properties. These attributes render MNCs highly advantageous for various applications. There is a range of methods designed to achieve precise control over their size, composition, and functional properties during their synthesis. Exploring synthetic approaches for MNCs is crucial, not just for their unique quantum size effects, but also for their widespread utility across multiple domains. By finely tuning the size, composition, and surface functionalities of MNCs, their physicochemical traits, including fluorescence, catalytic efficiency, and electronic behavior can be optimized well. Additionally, enhancing synthesis strategies is vital for bridging laboratory research with industrial implementation, thus establishing a basis for utilizing MNCs in multiple applications. This chapter offers a systematic review of the main synthetic approaches for MNCs, such as chemical reduction, ligand-induced etching, and template-assisted techniques, establishing a comprehensive framework for future advancements in this area.