Cations redistribution along the spiral of Ni-doped phyllosilicate nanoscrolls: energy modelling and STEM/EDS study.
Fiche publication
Date publication
janvier 2019
Journal
Chemphyschem : a European journal of chemical physics and physical chemistry
Auteurs
Membres identifiés du Cancéropôle Est :
Dr BELMONTE Thierry
Tous les auteurs :
Krasilin AA, Khrapova EK, Nomine A, Ghanbaja J, Belmonte T, Gusarov VV
Lien Pubmed
Résumé
Here we study a stress induced self-organization of Mg2+ and Ni2+ cations in the crystal structure of multiwalled (Mg1-x,Nix)3Si2O5(OH)4 phyllosilicate nanoscrolls. The phyllosilicate layer strives to compensate size and surface energy difference between the metal oxide and silica sheets by curling. But as soon as the layer grows, the scrolling mechanism becomes a spent force. An energy model proposes secondary compensation of strain: two cations distribute along the nanoscroll spiral in accordance with preferable radii of curvature. To reveal this, we study synthetic (Mg1-x,Nix)3Si2O5(OH)4 nanoscrolls by STEM/EDS technique. For a number of scrolls we have found indeed a change of Ni concentration with increase in distance from the nanoscroll central axis. The concentration gradient, according to our estimates, can reach 50 at.% over 25 nm of the wall thickness.
Mots clés
crystal growth, doping, electron microscopy, hydrothermal synthesis, phyllosilicates
Référence
Chemphyschem. 2019 Jan 10;: