Finding materials with high stability, high yield, and excellent catalytic performance has been an outstanding research challenge. Thiol-stabilized atomically precise metal nanoclusters (NCs) have attracted a lot of interest in recent years due to their unique properties and industrial applications, including catalysis, toxic metal-ion sensing, and magnetism. Unlike classical nanoparticles (NPs) which have larger sizes ranging between 10-100 nm, the size of nanoclusters typically ranges from 1 to 3 nm. Thus, nanoclusters represent good candidates to gain fundamental insights into optical and catalytic properties from the atomic to the molecular level. The majority of nanoclusters are based on Ag, Au, and more recently Cu. The major goal of this dissertation is the synthesis and structure determination of silver and copper nanoclusters. The first part of this dissertation addresses a shape-controlled synthesis strategy based on an isomeric dithiol ligand to yield the smallest crystallized silver nanocluster to date, formulated as Ag9. The second part discusses the preparation of different sizes of copper nanoclusters using a one-pot synthesis method and attempted to understand the structure-dependent catalytic pathways at the atomic level. Moreover, three novel Cu nanoclusters were developed: Cu29, Cu45, and Cu67. In terms of size, Cu67 represents a milestone towards high-nuclearity nanoclusters with interesting optical and structural properties. In terms of catalytic properties, Cu45 was found to be promising catalyst in hydroboration reactions of alkynes/alkenes and B2pin2, which affords hydroborated products with good to excellent yield. Mechanistic studies showed single-electron oxidation of an in-situ formed ate complex ([B2pin2]OH-) by the Cu45 catalyst, enabling hydroboration of unsaturated double bonds via a boryl-centred radical. These findings motivate us to extend the library of ligand-protected nanoclusters and focus deeply on exploiting metal nanoclusters based on Cu for catalysis.