Nonequilibrium thermodynamics of colloidal gold nanocrystals monitored by ultrafast electron diffraction and optical scattering microscopy

Burak Guzelturk, Aaron M. Lindenberg, James K. Utterback, Igor Coropceanu, Vladislav Kamysbayev, Eric M. Janke, Marc Zajac, Nuri Yazdani, Benjamin L. Cotts, Suji Park, Aditya Sood, Ming Fu Lin, Alexander H. Reid, Michael E. Kozina, Xiaozhe Shen, Stephen P. Weathersby, Vanessa Wood, Alberto Salleo, Xijie Wang, Dmitri V. TalapinNaomi S. Ginsberg

Research output: Contribution to journalArticlepeer-review

20 Scopus citations


Metal nanocrystals exhibit important optoelectronic and photocatalytic functionalities in response to light. These dynamic energy conversion processes have been commonly studied by transient optical probes to date, but an understanding of the atomistic response following photoexcitation has remained elusive. Here, we use femtosecond resolution electron diffraction to investigate transient lattice responses in optically excited colloidal gold nanocrystals, revealing the effects of nanocrystal size and surface ligands on the electron−phonon coupling and thermal relaxation dynamics. First, we uncover a strong size effect on the electron−phonon coupling, which arises from reduced dielectric screening at the nanocrystal surfaces and prevails independent of the optical excitation mechanism (i.e., inter- and intraband). Second, we find that surface ligands act as a tuning parameter for hot carrier cooling. Particularly, gold nanocrystals with thiol-based ligands show significantly slower carrier cooling as compared to amine-based ligands under intraband optical excitation due to electronic coupling at the nanocrystal/ ligand interfaces. Finally, we spatiotemporally resolve thermal transport and heat dissipation in photoexcited nanocrystal films by combining electron diffraction with stroboscopic elastic scattering microscopy. Taken together, we resolve the distinct thermal relaxation time scales ranging from 1 ps to 100 ns associated with the multiple interfaces through which heat flows at the nanoscale. Our findings provide insights into optimization of gold nanocrystals and their thin films for photocatalysis and thermoelectric applications.

Original languageEnglish (US)
Pages (from-to)4792-4804
Number of pages13
JournalACS Nano
Issue number4
StatePublished - Apr 28 2020

All Science Journal Classification (ASJC) codes

  • General Engineering
  • General Materials Science
  • General Physics and Astronomy


  • Colloidal nanocrystals
  • Electron−phonon coupling
  • Hot carriers
  • Ligands
  • Thermal transport
  • Time-resolved microscopy
  • Ultrafast electron diffraction


Dive into the research topics of 'Nonequilibrium thermodynamics of colloidal gold nanocrystals monitored by ultrafast electron diffraction and optical scattering microscopy'. Together they form a unique fingerprint.

Cite this