title: Influence of the Nanoscale Kirkendall Effect on the Morphology of Copper Indium Disulfide Nanoplatelets Synthesized by Ion Exchange.
abstract: CuInS2 nanocrystals are prepared by ion exchange with template Cu2-xS nanoplatelets and InX3 [X = chloride, iodide, acetate (OAc), or acetylacetonate (acac)]. The morphologies of the resultant nanocrystals depend on the InX3 precursor and the reaction temperature. Exchange with InCl3 at 150 °C produces CuInS2 nanoplatelets having central holes and thickness variations, whereas the exchange at 200 °C produces intact CuInS2 nanoplatelets in which the initial morphology is preserved. Exchange with InI3 at 150 °C produces CuInS2 nanoplatelets in which the central hollowing is more extreme, whereas exchange with In(OAc)3 or In(acac)3 at 150 °C produces intact CuInS2 nanoplatelets. The results establish that the ion exchange occurs through the thin nanoplatelet edge facets. The hollowing and hole formation are due to a nanoscale Kirkendall Effect operating in the reaction-limited regime for displacement of X(-) at the edges, to allow insertion of In(3+) into the template nanoplatelets.
authors.affiliation: Department of Chemistry, Washington University, St. Louis, Missouri 63130-4899, United States.
authors.forename: Linjia
authors.initials: L
authors.lastname: Mu
authors.affiliation: Department of Chemistry, Washington University, St. Louis, Missouri 63130-4899, United States.
authors.forename: Fudong
authors.initials: F
authors.lastname: Wang
authors.affiliation: Department of Chemistry, Washington University, St. Louis, Missouri 63130-4899, United States.
authors.forename: Bryce
authors.initials: B
authors.lastname: Sadtler
authors.affiliation: Department of Chemistry, Washington University, St. Louis, Missouri 63130-4899, United States.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Loomis
authors.affiliation: Department of Chemistry, Washington University, St. Louis, Missouri 63130-4899, United States.
authors.forename: William E
authors.initials: WE
authors.lastname: Buhro
keywords: cation exchange; copper(I) indium disulfide; copper(I) sulfide; hollow; nanoplatelets; nanoscale Kirkendall Effect