Honors & Awards
-
Stanford Interdisciplinary Graduate Fellowships, Stanford University (2019)
View details for DOI 10.1016/j.joule.2019.08.016
View details for Web of Science ID 000497987900024
View details for DOI 10.1016/j.matt.2019.06.001
View details for Web of Science ID 000519688200015
View details for DOI 10.1016/j.nanoen.2018.03.045
Oriented attachment of nanocrystalline subunits is recognized as a common crystallization pathway that is closely related to formation of nanoparticle superlattices, mesocrystals, and other kinetically stabilized structures. Approaching particles have been observed to rotate to achieve coalignment while separated by nanometer-scale solvent layers. Little is known about the forces that drive coalignment, particularly in this "solvent-separated" regime. To obtain a mechanistic understanding of this process, we used atomic-force-microscopy-based dynamic force spectroscopy with tips fabricated from oriented mica to measure the adhesion forces between mica (001) surfaces in electrolyte solutions as a function of orientation, temperature, electrolyte type, and electrolyte concentration. The results reveal an ∼60° periodicity as well as a complex dependence on electrolyte concentration and temperature. A continuum model that considers the competition between electrostatic repulsion and van der Waals attraction, augmented by microscopic details that include surface separation, water structure, ion hydration, and charge regulation at the interface, qualitatively reproduces the observed trends and implies that dispersion forces are responsible for establishing coalignment in the solvent-separated state.
View details for PubMedID 28679632
View details for PubMedCentralID PMC5530655
Latest information on COVID-19