Nanoscale goldbeating: Solid-state transformation of 0D and 1D gold nanoparticles to anisotropic 2D morphologies

Md Rubayat-E Tanjil; Tanuj Gupta; Matthew T Gole; Keegan P Suero; Zhewen Yin; Donald J McCleeary; Ossie R T Douglas; Maegen M Kincanon; Nicholas G Rudawski; Alissa B Anderson; Catherine J Murphy; Huijuan Zhao; Michael Cai Wang

doi:10.1093/pnasnexus/pgad267

Nanoscale goldbeating: Solid-state transformation of 0D and 1D gold nanoparticles to anisotropic 2D morphologies

PNAS Nexus. 2023 Aug 18;2(8):pgad267. doi: 10.1093/pnasnexus/pgad267. eCollection 2023 Aug.

Authors

Affiliations

¹ Department of Mechanical Engineering, University of South Florida, Tampa, FL 33620, USA.
² Department of Mechanical Engineering, Clemson University, Clemson, SC 29634-0921, USA.
³ Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
⁴ Herbert Wertheim College of Engineering Research Service Centers, University of Florida, Gainesville, FL 32611, USA.
⁵ Department of Chemistry, University of South Florida, Tampa, FL 33620, USA.
⁶ Department of Medical Engineering, University of South Florida, Tampa, FL 33620, USA.
⁷ Department of Chemical, Biological, and Materials Engineering, University of South Florida, Tampa, FL 33620, USA.

Abstract

Goldbeating is the ancient craft of thinning bulk gold (Au) into gossamer leaves. Pioneered by ancient Egyptian craftsmen, modern mechanized iterations of this technique can fabricate sheets as thin as ∼100 nm. We take inspiration from this millennia-old craft and adapt it to the nanoscale regime, using colloidally synthesized 0D/1D Au nanoparticles (AuNPs) as highly ductile and malleable nanoscopic Au ingots and subjecting them to solid-state, uniaxial compression. The applied stress induces anisotropic morphological transformation of AuNPs into 2D leaf form and elucidates insights into metal nanocrystal deformation at the extreme length scales. The induced 2D morphology is found to be dependent on the precursor 0D/1D NP morphology, size (0D nanosphere diameter and 1D nanorod diameter and length), and their on-substrate arrangement (e.g., interparticle separation and packing order) prior to compression. Overall, this versatile and generalizable solid-state compression technique enables new pathways to synthesize and investigate the anisotropic morphological transformation of arbitrary NPs and their resultant emergent phenomena.

Keywords: high-pressure compression; molecular dynamics; nanoparticle deformation.