John Cattermull

All Publications

• Characterisation and modelling of potassium-ion batteries. Nature communications Dhir, S., Cattermull, J., Jagger, B., Schart, M., Olbrich, L. F., Chen, Y., Zhao, J., Sada, K., Goodwin, A., Pasta, M. 2024; 15 (1): 7580

  Abstract

  Potassium-ion batteries (KIBs) are emerging as a promising alternative technology to lithium-ion batteries (LIBs) due to their significantly reduced dependency on critical minerals. KIBs may also present an opportunity for superior fast-charging compared to LIBs, with significantly faster K-ion electrolyte transport properties already demonstrated. In the absence of a viable K-ion electrolyte, a full-cell KIB rate model in commercial cell formats is required to determine the fast-charging potential for KIBs. However, a thorough and accurate characterisation of the critical electrode material properties determining rate performance-the solid state diffusivity and exchange current density-has not yet been conducted for the leading KIB electrode materials. Here, we accurately characterise the effective solid state diffusivities and exchange current densities of the graphite negative electrode and potassium manganese hexacyanoferrate K 2 Mn [ Fe ( CN ) 6 ] (KMF) positive electrode, through a combination of optimised material design and state-of-the-art analysis. Finally, we present a Doyle-Fuller-Newman model of a KIB full cell with realistic geometry and loadings, identifying the critical materials properties that limit their rate capability.

  View details for DOI 10.1038/s41467-024-51537-w

  View details for PubMedID 39217166

• Predicting Distortion Magnitudes in Prussian Blue Analogues JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Cattermull, J., Pasta, M., Goodwin, A. L. 2023; 145 (45): 24471-24475

  Abstract

  Based on simple electrostatic and harmonic potential considerations, we derive a straightforward expression linking the composition of a Prussian blue analogue (PBA) to its propensity to undergo collective structural distortions. We demonstrate the existence of a threshold value, below which PBAs are undistorted and above which PBAs distort by a degree that is controlled by a geometric tolerance factor. Our analysis rationalizes the presence, absence, and magnitude of distortions in a wide range of PBAs and distinguishes their structural chemistry from that of other hybrid perovskites.

  View details for DOI 10.1021/jacs.3c08752

  View details for Web of Science ID 001123576700001

  View details for PubMedID 37931061

  View details for PubMedCentralID PMC10655185

• K-Ion Slides in Prussian Blue Analogues JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Cattermull, J., Roth, N., Cassidy, S. J., Pasta, M., Goodwin, A. L. 2023; 145 (44): 24249-24259

  Abstract

  We study the phenomenology of cooperative off-centering of K+ ions in potassiated Prussian blue analogues (PBAs). The principal distortion mechanism by which this off-centering occurs is termed a "K-ion slide", and its origin is shown to lie in the interaction between local electrostatic dipoles that couple through a combination of electrostatics and elastic strain. Using synchrotron powder X-ray diffraction measurements, we determine the crystal structures of a range of low-vacancy K2M[Fe(CN)6] PBAs (M = Ni, Co, Fe, Mn, Cd) and establish an empirical link between composition, temperature, and slide-distortion magnitude. Our results reflect the common underlying physics responsible for K-ion slides and their evolution with temperature and composition. Monte Carlo simulations driven by a simple model of dipolar interactions and strain coupling reproduce the general features of the experimental phase behavior. We discuss the implications of our study for optimizing the performance of PBA K-ion battery cathode materials and also its relevance to distortions in other, conceptually related, hybrid perovskites.

  View details for DOI 10.1021/jacs.3c08751

  View details for Web of Science ID 001122384900001

  View details for PubMedID 37879069

  View details for PubMedCentralID PMC10636749

• Uncovering the Interplay of Competing Distortions in the Prussian Blue Analogue K₂Cu[Fe(CN)₆] CHEMISTRY OF MATERIALS Cattermull, J., Sada, K., Hurlbutt, K., Cassidy, S. J., Pasta, M., Goodwin, A. L. 2022; 34 (11): 5000-5008

  Abstract

  We report the synthesis, crystal structure, thermal response, and electrochemical behavior of the Prussian blue analogue (PBA) K2Cu[Fe(CN)6]. From a structural perspective, this is the most complex PBA yet characterized: its triclinic crystal structure results from an interplay of cooperative Jahn-Teller order, octahedral tilts, and a collective "slide" distortion involving K-ion displacements. These different distortions give rise to two crystallographically distinct K-ion channels with different mobilities. Variable-temperature X-ray powder diffraction measurements show that K-ion slides are the lowest-energy distortion mechanism at play, as they are the only distortion to be switched off with increasing temperature. Electrochemically, the material operates as a K-ion cathode with a high operating voltage and an improved initial capacity relative to higher-vacancy PBA alternatives. On charging, K+ ions are selectively removed from a single K-ion channel type, and the slide distortions are again switched on and off accordingly. We discuss the functional importance of various aspects of structural complexity in this system, placing our discussion in the context of other related PBAs.

  View details for DOI 10.1021/acs.chemmater.2c00288

  View details for Web of Science ID 000812128100001

  View details for PubMedID 35722203

  View details for PubMedCentralID PMC9202302

• Structural complexity in Prussian blue analogues MATERIALS HORIZONS Cattermull, J., Pasta, M., Goodwin, A. L. 2021; 8 (12): 3178-3186

  Abstract

  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 material KxMn[Fe(CN)6]y 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 other related systems, so as to aid in the design of next-generation PBA materials.

  View details for DOI 10.1039/d1mh01124c

  View details for Web of Science ID 000712450900001

  View details for PubMedID 34713885

  View details for PubMedCentralID PMC9326455

• High-entropy sulfide argyrodite electrolytes for all-solid-state lithium-sulfur batteries CELL REPORTS PHYSICAL SCIENCE Guo, H., Li, J., Burton, M., Cattermull, J., Liang, Y., Chart, Y., Rees, G. J., Aspinall, J., Pasta, M. 2024; 5 (10)

  View details for DOI 10.1016/j.xcrp.2024.102228

  View details for Web of Science ID 001337199700001

• Potassium Alloy Reference Electrodes for Potassium-Ion Batteries: The K-In and K-Bi Systems. ACS materials letters Jagger, B., Aspinall, J., Kotakadi, S., Cattermull, J., Dhir, S., Pasta, M. 2024; 6 (10): 4498-4506

  Abstract

  Potassium-ion batteries (KIBs) are a promising alternative to conventional lithium-ion batteries with reduced critical mineral dependency but accurate three-electrode characterization is hindered by the lack of a suitable reference electrode. Potassium metal is frequently used as a reference electrode out of necessity, but its high reactivity and unstable potential limit its reliability. Here we investigate the K-In and K-Bi alloy systems, synthesize two-phase In-In4K and Bi-Bi2K alloys, and identify Bi-Bi2K as a promising material owing to its stable potential of 1.07 V vs K+/K. We prove the use of Bi-Bi2K as a reference electrode by cycling graphite in three-electrode cells and demonstrate that it results in significantly less electrolyte reduction than potassium metal, facilitating the accurate electrochemical characterization necessary to accelerate KIB development.

  View details for DOI 10.1021/acsmaterialslett.4c01219

  View details for PubMedID 39391746

  View details for PubMedCentralID PMC11462602

• Local Structure and Dynamics in MPt(CN)6 Prussian Blue Analogues. Chemistry of materials : a publication of the American Chemical Society Harbourne, E. A., Barker, H., Guéroult, Q., Cattermull, J., Nagle-Cocco, L. A., Roth, N., Evans, J. S., Keen, D. A., Goodwin, A. L. 2024; 36 (11): 5796-5804

  Abstract

  We use a combination of X-ray pair distribution function (PDF) measurements, lattice dynamical calculations, and ab initio density functional theory (DFT) calculations to study the local structure and dynamics in various MPt(CN)6 Prussian blue analogues. In order to link directly the local distortions captured by the PDF with the lattice dynamics of this family, we develop and apply a new "interaction-space" PDF refinement approach. This approach yields effective harmonic force constants, from which the (experiment-derived) low-energy phonon dispersion relations can be approximated. Calculation of the corresponding Grüneisen parameters allows us to identify the key modes responsible for negative thermal expansion (NTE) as arising from correlated tilts of coordination octahedra. We compare our results against the phonon dispersion relations determined using DFT calculations, which identify the same NTE mechanism.

  View details for DOI 10.1021/acs.chemmater.4c01013

  View details for PubMedID 38883430

  View details for PubMedCentralID PMC11170939

• On the Origin of the Non-Arrhenius Na-ion Conductivity in Na3OBr. Angewandte Chemie (Weinheim an der Bergstrasse, Germany) Darminto, B., Rees, G. J., Cattermull, J., Hashi, K., Diaz-Lopez, M., Kuwata, N., Turrell, S. J., Milan, E., Chart, Y., Di Mino, C., Jeong Lee, H., Goodwin, A. L., Pasta, M. 2023; 135 (51): e202314444

  Abstract

  The sodium-rich antiperovskites (NaRAPs) with composition Na3OB (B=Br, Cl, I, BH4, etc.) are a family of materials that has recently attracted great interest for application as solid electrolytes in sodium metal batteries. Non-Arrhenius ionic conductivities have been reported for these materials, the origin of which is poorly understood. In this work, we combined temperature-resolved bulk and local characterisation methods to gain an insight into the origin of this unusual behaviour using Na3OBr as a model system. We first excluded crystallographic disorder on the anion sites as the cause of the change in activation energy; then identified the presence of a poorly crystalline impurities, not detectable by XRD, and elucidated their effect on ionic conductivity. These findings improve understanding of the processing-structure-properties relationships pertaining to NaRAPs and highlight the need to determine these relationships in other materials systems, which will accelerate the development of high-performance solid electrolytes.

  View details for DOI 10.1002/ange.202314444

  View details for PubMedID 38516325

• On the Origin of the Non-Arrhenius Na-ion Conductivity in Na₃OBr ANGEWANDTE CHEMIE-INTERNATIONAL EDITION Darminto, B., Rees, G. J., Cattermull, J., Hashi, K., Diaz-Lopez, M., Kuwata, N., Turrell, S. J., Milan, E., Chart, Y., Di Mino, C., Jeong Lee, H., Goodwin, A. L., Pasta, M. 2023; 62 (51): e202314444

  Abstract

  The sodium-rich antiperovskites (NaRAPs) with composition Na3 OB (B=Br, Cl, I, BH4 , etc.) are a family of materials that has recently attracted great interest for application as solid electrolytes in sodium metal batteries. Non-Arrhenius ionic conductivities have been reported for these materials, the origin of which is poorly understood. In this work, we combined temperature-resolved bulk and local characterisation methods to gain an insight into the origin of this unusual behaviour using Na3 OBr as a model system. We first excluded crystallographic disorder on the anion sites as the cause of the change in activation energy; then identified the presence of a poorly crystalline impurities, not detectable by XRD, and elucidated their effect on ionic conductivity. These findings improve understanding of the processing-structure-properties relationships pertaining to NaRAPs and highlight the need to determine these relationships in other materials systems, which will accelerate the development of high-performance solid electrolytes.

  View details for DOI 10.1002/anie.202314444

  View details for Web of Science ID 001105082700001

  View details for PubMedID 37902095

  View details for PubMedCentralID PMC10952800

• Filling vacancies in a Prussian blue analogue using mechanochemical post-synthetic modification CHEMICAL COMMUNICATIONS Cattermull, J., Wheeler, S., Hurlbutt, K., Pasta, M., Goodwin, A. L. 2020; 56 (57): 7873-7876

  Abstract

  Mechanochemical grinding of polycrystalline powders of the Prussian blue analogue (PBA) Mn[Co(CN)6]2/3□1/3·xH2O and K3Co(CN)6 consumes the latter and chemically modifies the former. A combination of inductively-coupled plasma and X-ray powder diffraction measurements suggests the hexacyanometallate vacancy fraction in this modified PBA is reduced by approximately one third under the specific conditions we explore. We infer the mechanochemically-driven incorporation of [Co(CN)6]3- ions onto the initially-vacant sites, coupled with intercalation of charge-balancing K+ ions within the PBA framework cavities. Our results offer a new methodology for the synthesis of low-vacancy PBAs.

  View details for DOI 10.1039/d0cc02922j

  View details for Web of Science ID 000549616400005

  View details for PubMedID 32529992