Journal article

When Like Destabilizes Like: Inverted Solvent Effects in Apolar Nanoparticle Dispersions

Debora Monego, Thomas Kister, Nicholas Kirkwood, David Doblas, Paul Mulvaney, Tobias Kraus, Asaph Widmer-Cooper

ACS Nano | American Chemical Society | Published : 2020


We report on the colloidal stability of nanoparticles with alkanethiol shells in apolar solvents. Small-angle X-ray scattering and molecular dynamics simulations were used to characterize the interaction between nanoparticles in linear alkane solvents ranging from hexane to hexadecane, including 4 nm gold cores with hexadecanethiol shells and 6 nm cadmium selenide cores with octadecanethiol shells. We find that the agglomeration is enthalpically driven and that, contrary to what one would expect from classical colloid theory, the temperature at which the particles agglomerate increases with increasing solvent chain length. We demonstrate that the inverted trend correlates with the temperatur..

View full abstract

University of Melbourne Researchers


Awarded by ARC Centre of Excellence in Exciton Science

Awarded by Australian Research Council

Funding Acknowledgements

P.M., N.K., D.M., and A.W. were supported by the ARC Centre of Excellence in Exciton Science (CE170100026). A.W. thanks the Australian Research Council for a Future Fellowship (FT140101061), and D.M. thanks the University of Sydney Nano Institute for a Postgraduate Top-Up Scholarship and the Australian Nanotechnology Network for an Overseas Travel Fellowship. Computational resources were generously provided by the University of Sydney HPC service, the National Computational Infrastructure National Facility (NCINF) Flagship program, and the Pawsey Supercomputer Centre Energy and Resources Merit Allocation Scheme. T.K., D.D., and T.K. thank the DFG Deutsche Forschungsgemeinschaft for funding. P.M. and T.K. also thank the DAAD for travel support.