Spontaneous Carbon-Support-Induced Metal Deposition

Recent investigations have demonstrated the possibility for spontaneous deposition of noble metal nanoparticles from corresponding metal ion solutions on carbon supports, in the absence of additional reductants in the experimental systems. This process is a result of a direct redox reaction between the solute metal species and the carbon materials and differs from the typical electroless plating, the latter requiring additional reducing agents or catalysts to drive the reduction reaction. Due to the diversity of the used carbon materials including both dispersed nanostructured carbons and supported electrode-like carbon materials and the different approaches to follow the process and characterize the products, these studies are scattered in the scientific literature. The aim of the present review is to put these diverse investigations in a common context and focus on the existing experimental findings, the ways to monitor and control the process, and the general concept. Some aspects that need to be further corroborated are outlined in view of the involvement of the spontaneous redox process as a practical tool for the development of new catalysts.