title: Synergy in photomagnetic/ferromagnetic sub-50 nm core-multishell nanoparticles.
abstract: Based on nickel hexacyanidochromate and cobalt hexacyanidoferrate Prussian blue analogues, two series of photomagnetic/ferromagnetic sub-50 nm core multishell coordination nanoparticles have been synthesized in a surfactant-free one-pot multistep procedure with good control over the dispersity (10% standard deviation) and good agreement with the targeted size at each step. The composition and the valence state of each shell have been probed by different techniques that have revealed the predominance of Co(II)-NC-Fe(III) pairs in a series synthesized without alkali while Co(III)-NC-Fe(II) photoswitchable pairs have been successfully obtained in the photoactive coordination nanoparticles by control of Cs(+) insertion. When compared, the photoinduced behavior of the latter compound is in good agreement with that of the model one. Exchange coupling favors a uniform reversal of the magnetization of the heterostructured nanoparticles, with a large magnetization brought by a soft ferromagnetic shell and a large coercivity due to a harder photomagnetic shell. Moreover, a persistent increase of the photoinduced magnetization is observed for the first time up to the ordering temperature (60 K) of the ferromagnetic component because of a unique synergy.
authors.affiliation: Institut de Chimie Moléculaire et des Matériaux d'Orsay, rue du Doyen Poitou, Université Paris Sud 11 , 91405 Orsay, France.
authors.forename: Nada
authors.initials: N
authors.lastname: Dia
authors.forename: Laurent
authors.initials: L
authors.lastname: Lisnard
authors.forename: Yoann
authors.initials: Y
authors.lastname: Prado
authors.forename: Alexandre
authors.initials: A
authors.lastname: Gloter
authors.forename: Odile
authors.initials: O
authors.lastname: Stéphan
authors.forename: François
authors.initials: F
authors.lastname: Brisset
authors.forename: Hala
authors.initials: H
authors.lastname: Hafez
authors.forename: Zeinab
authors.initials: Z
authors.lastname: Saad
authors.forename: Corine
authors.initials: C
authors.lastname: Mathonière
authors.forename: Laure
authors.initials: L
authors.lastname: Catala
authors.forename: Talal
authors.initials: T
authors.lastname: Mallah