Large-scale synthesis and surface plasmon resonance properties of angled silver/silver homojunction nanowires

Angled silver/silver (Ag/Ag) homojunc- tion nanowires (HNWs) with an average diameter of about 72 nm have been prepared by a straightforward and effective solvothermal method. The synthesis involves a one-step, non-seed, and template-less process to large-scale Ag/Ag HNWs, which is low- cost and proceeds at moderate temperatures. Two neighboring Ag nanorods or nanowires were con- nected into obtuse angle by Ag/Ag homojunction. It was found that synthesizing Ag/Ag HNWs were very sensitive to reaction temperature and polyvinylpyrrol- idone concentration. Only through finely controlling these reaction parameters, the high-quality Ag/Ag HNWs could be formed in large scale and their surface plasmon resonance properties could be effectively tailored. High-resolution transmission electron micros- copy and selected area electron diffraction investiga- tions showed that the Ag/Ag HNWs were generated with a twinned crystalline structure. We also proposed a primary experimental model to illustrate the growth mechanism of the angled Ag/Ag HNWs.