Supporting Information. Real-Time Dark-Field Scattering Microscopic Monitoring of. the in situ Growth of Single Nanoalloys

Transcription

1 Supporting Information for Real-Time Dark-Field Scattering Microscopic Monitoring of the in situ Growth of Single Nanoalloys Yue Liu,, and Cheng Zhi Huang,,* Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing , China; College of Pharmaceutical Sciences, Southwest University, Chongqing , China. Present Address: Department of Chemistry, College of Pharmaceutical Sciences, Third Military Medical University, Chongqing , China; * chengzhi@swu.edu.cn.

2 Figure S1. (A) Dark-field light scattering and (B) SEM images the same collection of Ag nanoparticles. The inserts in B are the enlarged SEM images of the corresponding nanoparticles. The particle scattering blue, cyan, and yellow lights are nanosphere, nanocubes, and triangular nanobipyramids.

3 Figure S2. A large scale dark-field light scattering images of the same collection of Ag nanoparticles before (A) and after (B) their exposure to growth solution for 5 min. Before growth, Ag nanoparticles scattered a variety of light, such as red, yellow, cyan, and blue. However, all nanoparticles turned as cyan-green with some white particles.

4 Figure S3. Resonant scattering spectra of an Ag nanorod before (black curves) and after (red curves) their incubation with ascorbic acid for 5 min. No significant change in spectrum was observed after the treatment of ascorbic acid.

5 Figure S4. Dark-field light scattering images of Ag nanoparticles of the same area before (A) and after (B) their exposure to mol/l HgCl 2 for 5 min. Ag nanoparticles disappeared after incubation.

6 Figure S5. (A) SEM images of Ag nanoparticles after treated with growth solution for 20 min. (B) Magnified SEM images of the numbered nanoparticles in A. One can see that the formed nanoparticles are all spheres, no specially shaped particles were observed.

7 Figure S6. SEM images of different shaped Ag nanoparticles (A) before and (B) after treated with growth solution for 20 min. Before growth, Ag nanoparticles have special shapes, such as rod, cube, and triangular bipyramid. However, the same nanoparticles turned to be spheres after growth. Particle 4 is a rod, and changed to sphere, exhibiting significant decrease of aspect ratio. The corners of Particle 6 and 7 were rounded.

8 Figure S7. Characterization of the particle size as a function of growth time. (A) Representative SEM images of Ag nanoparticles at different growth stages: 0, 120, 300, 480, 720, 1200 s; (B) Statistical particle size as a function of growth time. S 0 is the particle size at 0 s, and S t is the size at different growth time. The error bars were calculated form 60 particles. The scale bar is 100 nm for all images.

9 Figure S8. Real-time watching the growth of single nanoalloys from Ag triangular bipyramids using dark-field scattering microscopy and spectroscopy. (A) Time-dependent dark-field light scattering images and (B) corresponding resonant scattering spectra of a representative Ag triangular bipyramid after its exposure to growth solution. C and D show the scattering wavelength peak and scattering intensity changes as a function of incubation time. The scale bar is 1 µm for all images.

10 Figure S9. Real-time watching the growth of single nanoalloys from Ag nanocubes using dark-field scattering microscopy and spectroscopy. (A) Time-dependent dark-field light scattering images and (B) corresponding resonant scattering spectra of a representative Ag nanocube after its exposure to growth solution. C and D show the scattering wavelength peak and scattering intensity changes as a function of incubation time. The scale bar is 1 µm for all images.

11 Figure S10. A simulative picture of simply home-made flow cell. The flow cell consists of slide glass and cover glass. Slide glass was used for the substrate and two small cover glasses were placed above it, then covered with another cover glass, which gave birth to a small cell.