title: Selective cation exchange in the core region of Cu2-xSe/Cu2-xS core/shell nanocrystals.
abstract: We studied cation exchange (CE) in core/shell Cu2-xSe/Cu2-xS nanorods with two cations, Ag(+) and Hg(2+), which are known to induce rapid exchange within metal chalcogenide nanocrystals (NCs) at room temperature. At the initial stage of the reaction, the guest ions diffused through the Cu2-xS shell and reached the Cu2-xSe core, replacing first Cu(+) ions within the latter region. These experiments prove that CE in copper chalcogenide NCs is facilitated by the high diffusivity of guest cations in the lattice, such that they can probe the whole host structure and identify the preferred regions where to initiate the exchange. For both guest ions, CE is thermodynamically driven as it aims for the formation of the chalcogen phase characterized by the lower solubility under the specific reaction conditions.
authors.affiliation: Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy.
authors.forename: Karol
authors.initials: K
authors.lastname: Miszta
authors.affiliation: Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy.
authors.forename: Graziella
authors.initials: G
authors.lastname: Gariano
authors.affiliation: Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy.
authors.forename: Rosaria
authors.initials: R
authors.lastname: Brescia
authors.affiliation: Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy.
authors.forename: Sergio
authors.initials: S
authors.lastname: Marras
authors.affiliation: Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: De Donato
authors.affiliation: Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Ghosh
authors.affiliation: Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: De Trizio
authors.affiliation: Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy.
authors.forename: Liberato
authors.initials: L
authors.lastname: Manna