The effect of cation substitution on the local coordination of protons in Ba2In1.85M0.15O6H2 (M = In, Ga, Sc and Y)
Artikel i vetenskaplig tidskrift, 2021

We report on an investigation of the local structure and vibrational dynamics in the brownmillerite-based proton conductors Ba2In1.85M0.15O6H2 with M = In, Ga, Sc and Y. The aim is to determine the effect of the cation (M) substitution on the local coordination environment of the protons. The techniques used are infrared spectroscopy and inelastic neutron scattering. The materials are characterized by two main types of proton sites, denoted as H (1) and H(2), which are featured by different local structures. We establish that the relative population of these two proton sites varies as a function of M. Specifically, it is found that, with respect to Ba2In2O6H2, the relative population of H(1) protons increases upon the substitution of In with any of the three different cations. The strongest effect is observed for M = Ga and Sc, whereas the effect observed for M = Y is minor. This new insight motivates efforts to unravel the mobility of the two types of protons, since then cation modification would offer a rational route for improving the proton conductivity of these types of materials.

Brownmillerite-based oxides

Cation substitution

Local structure

Vibrational spectroscopy

Proton sites

Författare

Laura Mazzei

Chalmers, Kemi och kemiteknik, Energi och material

Fabio Piccinelli

Universita degli Studi di Verona

Marco Bettinelli

Universita degli Studi di Verona

Stewart F. Parker

STFC Rutherford Appleton Laboratory

Maths Karlsson

Chalmers, Kemi och kemiteknik, Energi och material

Solid State Ionics

0167-2738 (ISSN)

Vol. 365 115624

Ny förståelse om väteinnehållande material för energi

Vetenskapsrådet (VR) (621-2010-3519), 2011-01-01 -- 2016-12-31.

Vetenskapsrådet (VR) (621-2010-3519), 2011-01-01 -- 2016-12-31.

Ämneskategorier

Oorganisk kemi

Keramteknik

Teoretisk kemi

DOI

10.1016/j.ssi.2021.115624

Mer information

Senast uppdaterat

2021-06-29