On the Existence of A‐Site Deficiency in Perovskites and Its Relation to the Electrochemical Performance

The low range of A-site deficiency in perovskite structures with Ni cations was verified by neutron powder diffraction, transmission electron microscopy, and thermogravimetric analysis. A thermodynamic approach has been utilized, for the first time, to predict the extent of A-site deficiencies within the perovskite structure, introducing simple prediction criteria that could be adopted for designing advanced materials. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.