Cation Redistribution along the Spiral of Ni‐Doped Phyllosilicate Nanoscrolls: Energy Modelling and STEM/EDS Study1. Issue 5 (1st February 2019)

• Record Type: Journal Article
• Authors: Krasilin, Andrei A.; Khrapova, Ekaterina K.; Nominé, Alexandre; Ghanbaja, Jaafar; Belmonte, Thierry; Gusarov, Victor V.
• Is Part Of: Chemphyschem. Volume 20:Issue 5(2019)
• Page Start: 719
• Page End: 726
• Publication Date: 2019-02-01
• Subjects: crystal growth -- doping -- electron microscopy -- hydrothermal synthesis -- phyllosilicates; Chemistry, Physical and theoretical -- Periodicals; 541.05
• DOI: 10.1002/cphc.201801144
• Languages: English
• ISSNs: 1439-4235

Abstract

Abstract: Here, we study the stress‐induced self‐organization of Mg 2+ and Ni 2+ cations in the crystal structure of multiwalled (Mg1– x, Ni x )3 Si2 O5 (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, Ni x )3 Si2 O5 (OH)4 nanoscrolls by the scanning transmission electron microscopy/energy‐dispersive X‐ray spectroscopy (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. Abstract : Changes in Ni concentration within synthetic (Mg1– x Ni x )3 Si2 O5 (OH)4 nanoscrolls are observed by scanning transmission electron microscopy/energy‐dispersive spectroscopy. An energy model is developed to prove the possibility of Mg and Ni cation distribution along the nanoscroll spiral.