Localized surface plasmon resonance induced assembly of bimetal nanochains.

Bimetal nanochains (NCs) are attracting increasing attention in the fields of catalysis and electrocatalysis due to the synergistic effects in electronic and optical properties, but the fabrication of bimetal NCs remains challenging. Here, we report a general strategy named "nucleation in the irradiation then growth in the dark" for the preparation of Au/M (second metal) NCs. In the irradiation stage, the localized surface plasmon resonance (LSPR) effect of Au NPs is excited to overcome the nucleation energy barrier for the deposition of second metals (Pt, Ag and Pd). In the followed dark process, the preferential growth of second metals on the existed nucleus leads to the formation of nanochain rather than the core/shell nanostructure. In the model reaction of electrocatalytic hydrogen evolution, the optimized Au/Pt NCs showed much better performance compared with the commercial Pt/C.