Journal Home > Volume 15 , Issue 2

Understanding the surface processes (deposition and surface diffusion) that occur at or close to the surface of growing nanoparticles is important for fabricating reproducibly stellated or branched gold nanoparticles with precise control over arm length and spatial orientation of arms around the core. By employing a simple seed-mediated strategy, we investigate the key synthetic variables for precise tuning of in situ surface processes (competition between the deposition and surface diffusion). These variables include the reduction rate of a reaction, the packing density of molecules/ions on the high surface energy facets, and temperature. As a result, the thermodynamically stabilized nanoparticles (cuboctahedron and truncated cube) and kinetic products (cube, concave cube, octapod, stellated octahedron, and rhombic dodecahedron) in different sizes with high quantitative shape yield (> 80%) can be obtained depending on the reduction rate of reaction and the packing density of molecules/ions. With computer simulation, we studied the stability of stellated (branched structure) and non-stellated (non-branched structure) gold nanoparticles at high temperature. We construct a morphology phase diagram by varying different synthetic parameters, illustrating the formation of both stellated and non-stellated gold nanoparticles in a range of reaction conditions. The stellated gold nanoparticles display shape-dependent optical properties and can be self-assembled into highly ordered superstructures to achieve an enhanced plasmonic response. Our strategy can be applied to other metal systems, allowing for the rational design of advanced new stellated metal nanoparticles with fascinating symmetry dependent plasmonic, catalytic, and electronic properties for technological applications.

Video
12274_2021_3635_MOESM2_ESM.mp4
File
12274_2021_3635_MOESM1_ESM.pdf (4.4 MB)
Publication history
Copyright
Acknowledgements

Publication history

Received: 05 April 2021
Revised: 19 May 2021
Accepted: 30 May 2021
Published: 11 August 2021
Issue date: February 2022

Copyright

© Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2021

Acknowledgements

Acknowledgements

The authors gratefully acknowledge the financial support of the Australian Research Council and the Australian National Health and Medical Research Council. The authors acknowledge the Australian Centre for Microscopy and Microanalysis, and the Sydney Nano, University of Sydney with technical support for the materials characterization. Authors would like to thank IITM-UniSyd Global alliance for partial research support.

Return