In most cases, a range of additives are required to stabilize the NPs prepared by the so-called colloidal methods . Although these additives / surfactants / ligands can bring desirable functionality to the NC , they are in most cases detrimental . Indeed, such molecules interact with atom at the surface of the NPs which are then less available to reactants. This drawback becomes critical for the development of NCs made of expensive materials such as precious metals. To maximize the catalyst activity, these additives often need to be removed, typically by tedious steps with often limited success, and with the risk to modify the properties of the as-prepared NPs .