In this recently published work, a collaboration between Laboratory of Electron Nanoscopies (LENS)- Micro and Nanotechnology and nanoscopies for Electronic and Electrophotonic devices (MIND) and Laboratory of Nanostructured and Nanocomposite Materials (LM2N), they developed a new and straightforward colloidal synthetic way to form hybrid Au−Ag2X (X = S, Se) nanoparticles under mild conditions through the direct reaction of Au and Ag2X nanocrystals in solution. The mechanism and forces driving the reaction have been studied in detail with the help of advanced electron microscopy techniques and DFT calculations. The collected data indicate that the formation of a highly stable AuAg3X2 ternary phase is responsible for the selective heteroattachment of Au and Ag2X nanocrystals, followed by the occurrence of a solid-state electrochemical exchange at the interface between the two domains, resembling an antigalvanic replacement reaction. The extension of the methodology to other technologically relevant materials is expected to enhance the consolidation of interfaces in solid nanostructured composites and thin films, improving in this way the transport properties in optoelectronic, thermoelectric, and catalytic devices.
Spontaneous Hetero-attachment of Single-Component Colloidal Precursors for the Synthesis of Asymmetric Au–Ag2X (X = S, Se) Heterodimers M. Lin, G. Montana, J. Blanco, L. Yedra, H. van Gog, M. A. van Huis, Mi. López-Haro, J. J. Calvino, S.Estradé, F. Peiró, and A. Figuerola. Chemistry of Materials, 2022