Exsolution of SrO during the topochemical conversion of $LaSr_{3}CoRuO_{8}$ to the Oxyhydride $LaSr_{3}CoRuO_{4}H_{4}$

Reaction of the n = 1 Ruddlesden-Popper oxide LaSr3CoRuO8 with CaH2 yields the oxyhydride phase LaSr3CoRuO4H4 via a topochemical anion exchange. Close inspection of the X-ray and neutron powder diffraction data in combination with HAADF-STEM images reveals that the nanoparticles of SrO are exsolved from the system during the reaction, with the change in cation stoichiometry accommodated by the inclusion of n > 1 (Co/Ru)(n)On+1H2n "perovskite" layers into the Ruddlesden-Popper stacking sequence. This novel pseudotopochemical process offers a new route for the formation of n > 1 Ruddlesden-Popper structured materials. Magnetization data are consistent with a LaSr3Co+Ru2+O4H4 (Co+, d(8), S = 1; Ru2+, d(6), S = 0) oxidation/spin state combination. Neutron diffraction and mu+SR data show no evidence for long-range magnetic order down to 2 K, suggesting the diamagnetic Ru2+ centers impede the Co-Co magnetic-exchange interactions.

Publication year:2019

Keywords:A1 Journal article

BOF-keylabel:yes

BOF-publication weight:6

CSS-citation score:1

Authors:International

Authors from:Higher Education

Accessibility:Open