Structural complexity in Prussian blue analogues

A composite of magnified materials employed in the research

We survey the most important kinds of structural complexity in Prussian blue analogues, their implications for materials function, and how they might be controlled through judicious choice of composition.

We focus on six particular aspects: octahedral tilts, A-site 'slides', Jahn-Teller distortions, A-site species and occupancy, hexacyanometallate vacancies, and framework hydration.

The promising K-ion cathode Materials K2Mn[Fe(CN)6] serves as a recurrent example that illustrates many of these different types of complexity.

Our article* concludes with a discussion of how the interplay of various distortion mechanisms might be exploited to optimise the performance of this and this and other related systems, so as to aid in the design of next-generation PBA materials.

* 'Structural complexity in Prussian blue analogues' published in Materials Horizons - Issue 12 (2021).

Authors: John Cattermull, Professor Mauro Pasta and Professor Andrew Goodwin.