Professor John Evans' Outputs (109)

Probing dynamic oxygen exchange for hydrogen production with operando neutron diffraction (2025)
Journal Article
Telford, D. M., Martínez Martín, A., Guy, M. D., Henry, P. F., Jones, M. O., Hu, W., Metcalfe, I. S., & Evans, J. S. O. (online). Probing dynamic oxygen exchange for hydrogen production with operando neutron diffraction. Nature Chemical Engineering, https://doi.org/10.1038/s44286-025-00231-9

A chemical looping process exploiting the variable oxygen content of ABO3−δ perovskite materials can achieve super-equilibrium conversions of societally important reactions such as the water–gas shift reaction (CO + H2O ⇋ CO2 + H2). The approach reli... Read More about Probing dynamic oxygen exchange for hydrogen production with operando neutron diffraction.

Exploitation of pseudo-symmetry in the Cambridge Structural Database for molecular ferroelectric discovery (2025)
Journal Article
Thompson, S. Y., Stokes, H. T., Campbell, B. J., Goldberg, E. D., & Evans, J. S. O. (online). Exploitation of pseudo-symmetry in the Cambridge Structural Database for molecular ferroelectric discovery. CrystEngComm, https://doi.org/10.1039/d5ce00445d

The search for new useful molecular ferroelectrics is a non-trivial problem. We present the application of an automated symmetry-searching method (FERROSCOPE) to the Cambridge Structural Database (CSD) in order to identify polar structures with a clo... Read More about Exploitation of pseudo-symmetry in the Cambridge Structural Database for molecular ferroelectric discovery.

A “waste” of time?: the synthesis of a magnesium-substituted aluminophosphate from an unconventional source of magnesium (2025)
Journal Article
Crockett, C. H., Bedward, J. R., Clayton, P. K., Evans, J. S. O., Greenwell, H. C., & Taylor, R. A. (online). A “waste” of time?: the synthesis of a magnesium-substituted aluminophosphate from an unconventional source of magnesium. Dalton Transactions, https://doi.org/10.1039/d5dt00694e

Magnesium-substituted microporous aluminophosphates (MgAlPOs) are tuneable framework materials that exhibit strong Brønsted acidity and have found great utility as catalysts for a wide variety of green transformations. Typically, refined magnesium sa... Read More about A “waste” of time?: the synthesis of a magnesium-substituted aluminophosphate from an unconventional source of magnesium.

Average and Local Structure of La 1– x Sr x Fe 1– y Mn y O 3−δ Chemical Looping Oxygen Carrier Materials (2025)
Journal Article
Telford, D., Hu, W., Metcalfe, I. S., Jones, M. O., Henry, P. F., & Evans, J. S. O. (2025). Average and Local Structure of La 1– x Sr x Fe 1– y Mn y O 3−δ Chemical Looping Oxygen Carrier Materials. Chemistry of Materials, 37(9), 3471-3482. https://doi.org/10.1021/acs.chemmater.5c00388

Nonstoichiometric mixed-metal oxides in the La1–x Sr x Fe1–y Mn y O3 –δ family are promising oxygen carrier materials for chemical looping processes, including clean hydrogen production from the water-gas shift reaction. The crystal structure variati... Read More about Average and Local Structure of La 1– x Sr x Fe 1– y Mn y O 3−δ Chemical Looping Oxygen Carrier Materials.

Oxide Ion Dynamics and Structure–Property Relationships in A 3 OhTd 2 O 7.5 Ionic Conductors (A = Ba, Sr; Oh = Y; Td = Ga, Zn) (2025)
Journal Article
Wagstaff, O., Avdeev, M., Clark, S. J., Evans, J. S. O., & Evans, I. R. (2025). Oxide Ion Dynamics and Structure–Property Relationships in A 3 OhTd 2 O 7.5 Ionic Conductors (A = Ba, Sr; Oh = Y; Td = Ga, Zn). Chemistry of Materials, 37(9), 3492-3503. https://doi.org/10.1021/acs.chemmater.5c00426

A3OhTd2O7.5 materials (where Oh/Td = 6/4 coordinate metal ions) are a new class of ionic conductors, with potential applications in important technologies such as fuel cells. We report the first results of ab initio molecular dynamics simulations of... Read More about Oxide Ion Dynamics and Structure–Property Relationships in A 3 OhTd 2 O 7.5 Ionic Conductors (A = Ba, Sr; Oh = Y; Td = Ga, Zn).

Displacive Jahn–Teller Transition in NaNiO 2 (2024)
Journal Article
Nagle-Cocco, L. A. V., Genreith-Schriever, A. R., Steele, J. M. A., Tacconis, C., Bocarsly, J. D., Mathon, O., Neuefeind, J. C., Liu, J., O’Keefe, C. A., Goodwin, A. L., Grey, C. P., Evans, J. S. O., Dutton, S. E., Nagle-Cocco, L. A. V., Steele, J. M. A., Neuefeind, J. C., Goodwin, A. L., Grey, C. P., & Dutton, S. E. (2024). Displacive Jahn–Teller Transition in NaNiO 2. Journal of the American Chemical Society, 146(43), 29560-29574. https://doi.org/10.1021/jacs.4c09922

Below its Jahn–Teller transition temperature, T JT, NaNiO2 has a monoclinic layered structure consisting of alternating layers of edge-sharing NaO6 and Jahn–Teller-distorted NiO6 octahedra. Above T JT where NaNiO2 is rhombohedral, diffraction measure... Read More about Displacive Jahn–Teller Transition in NaNiO 2.

Local Structure and Dynamics in MPt(CN) 6 Prussian Blue Analogues (2024)
Journal Article
Harbourne, E., Barker, H., Guéroult, Q., Cattermull, J., Nagle-Cocco, L. A. V., Roth, N., Evans, J. S. O., Keen, D. A., & Goodwin, A. L. (2024). Local Structure and Dynamics in MPt(CN) 6 Prussian Blue Analogues. Chemistry of Materials, 36(11), 5796-5804. https://doi.org/10.1021/acs.chemmater.4c01013

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 analo... Read More about Local Structure and Dynamics in MPt(CN) 6 Prussian Blue Analogues.

Structural dynamics of first-order phase transition in giant magnetocaloric La(Fe,Si)13: The free energy landscape (2024)
Journal Article
Beleza, A. A., Pires, B., Almeida, R., Evans, J. S. O., dos Santos, A. M., Frontzek, M., …Belo, J. H. (2024). Structural dynamics of first-order phase transition in giant magnetocaloric La(Fe,Si)13: The free energy landscape. Materials Today Physics, 42, Article 101388. https://doi.org/10.1016/j.mtphys.2024.101388

Maximizing the performance of magnetic refrigerators and thermomagnetic energy harvesters is imperative for their successful implementation and can be done by maximizing their operation frequency. One of the features delimiting the frequency and effi... Read More about Structural dynamics of first-order phase transition in giant magnetocaloric La(Fe,Si)13: The free energy landscape.

Extensive Polymorphism in the Molecular Ferroelectric 18-Crown-6 Oxonium Tetrachloro-Gallium(III) (2023)
Journal Article
Thompson, S. Y., Devenney, L. A., Yufit, D. S., & Evans, J. S. (2023). Extensive Polymorphism in the Molecular Ferroelectric 18-Crown-6 Oxonium Tetrachloro-Gallium(III). Crystal Growth and Design, 23(4), 2860-2869. https://doi.org/10.1021/acs.cgd.3c00017

The materials property of ferroelectricity is intimately linked with symmetry-changing phase transitions. Characterizing such transitions is therefore essential for understanding molecular ferroelectrics. In this paper, we explore the temperature and... Read More about Extensive Polymorphism in the Molecular Ferroelectric 18-Crown-6 Oxonium Tetrachloro-Gallium(III).

Tailoring Negative Thermal Expansion via Tunable Induced Strain in La–Fe–Si-Based Multifunctional Material (2022)
Journal Article
Fleming, R. O., Gonçalves, S., Davarpanah, A., Radulov, I., Pfeuffer, L., Beckmann, B., Skokov, K., Ren, Y., Li, T., Evans, J., Amaral, J., Almeida, R., Lopes, A., Oliveira, G., Araújo, J. P., Apolinário, A., & Belo, J. H. (2022). Tailoring Negative Thermal Expansion via Tunable Induced Strain in La–Fe–Si-Based Multifunctional Material. ACS Applied Materials and Interfaces, 14(38), 43498-43507. https://doi.org/10.1021/acsami.2c11586

Zero thermal expansion (ZTE) composites are typically designed by combining positive thermal expansion (PTE) with negative thermal expansion (NTE) materials acting as compensators and have many diverse applications, including in high-precision instru... Read More about Tailoring Negative Thermal Expansion via Tunable Induced Strain in La–Fe–Si-Based Multifunctional Material.

Defects and disorder in apatite-type silicate oxide ion conductors: implications for conductivity (2022)
Journal Article
Fuller, C. A., Gutmann, M. J., Ling, C. D., Wang, C.-H., Zhang, W., Halasyamani, P. S., Evans, I. R., & Evans, J. S. (2022). Defects and disorder in apatite-type silicate oxide ion conductors: implications for conductivity. Journal of Materials Chemistry A: materials for energy and sustainability, 10(27), https://doi.org/10.1039/d2ta02328h

The structure and composition of La-silicate apatite oxide ion conductor, La10Si6O27, in which the types of defects it contains are controversial, has been thoroughly investigated. Large crystals were grown using the floating zone method, and their s... Read More about Defects and disorder in apatite-type silicate oxide ion conductors: implications for conductivity.

Oxide ion conductivity, proton conductivity and phase transitions in perovskite-derived Ba3–xSrxYGa2O7.5 0  x  3 materials (2022)
Journal Article
Fuller, C. A., Murrell, J. I., Blom, D. A., Vogt, T., Zhang, W., Halasyamani, P. S., Radosavljevic Evans, I., & Evans, J. S. (2022). Oxide ion conductivity, proton conductivity and phase transitions in perovskite-derived Ba3–xSrxYGa2O7.5 0  x  3 materials. Chemistry of Materials, 34(7), 3185-3196. https://doi.org/10.1021/acs.chemmater.1c04372

We report the synthesis, structural characterization, oxide ion and proton conductivities of the perovskite-related Ba3–xSrxYGa2O7.5 family. Single-phase samples are prepared for 0  x  3 and show a complex structural evolution from P2/c to C2 space... Read More about Oxide ion conductivity, proton conductivity and phase transitions in perovskite-derived Ba3–xSrxYGa2O7.5 0  x  3 materials.

Solid State Materials Chemistry (2021)
Book
Woodward, P. M., Karen, P., Evans, J. S., & Vogt, T. (2021). Solid State Materials Chemistry. https://doi.org/10.1017/9781139025348

Oxide Ion and Proton Conductivity in a Family of Highly Oxygen-Deficient Perovskite Derivatives (2021)
Journal Article
Fuller, C. A., Blom, D. A., Vogt, T., Radosavljevic Evans, I., & Evans, J. S. (2022). Oxide Ion and Proton Conductivity in a Family of Highly Oxygen-Deficient Perovskite Derivatives. Journal of the American Chemical Society, 144(1), 615-624. https://doi.org/10.1021/jacs.1c11966

Functional oxides showing high ionic conductivity have many important technological applications. We report oxide ion and proton conductivity in a family of perovskite-related compounds of the general formula A3OhTd2O7.5, where Oh is an octahedrally... Read More about Oxide Ion and Proton Conductivity in a Family of Highly Oxygen-Deficient Perovskite Derivatives.

Production of high purity H2 through chemical-looping water–gas shift at reforming temperatures – The importance of non-stoichiometric oxygen carriers (2021)
Journal Article
de Leeuwe, C., Hu, W., Evans, J., von Stosch, M., & Metcalfe, I. S. (2021). Production of high purity H2 through chemical-looping water–gas shift at reforming temperatures – The importance of non-stoichiometric oxygen carriers. Chemical Engineering Journal, 423, https://doi.org/10.1016/j.cej.2021.130174

H2 is an important feedstock for many industrial processes and could be used as an energy carrier in a low carbon economy. This means that carbon neutral methods for H2 production are of vital importance. Chemical looping allows for H2 production wit... Read More about Production of high purity H2 through chemical-looping water–gas shift at reforming temperatures – The importance of non-stoichiometric oxygen carriers.

Structure Analysis from Powder Diffraction Data: Rietveld Refinement in Excel (2020)
Journal Article
Evans, J. S., & Radosavljevic Evans, I. (2021). Structure Analysis from Powder Diffraction Data: Rietveld Refinement in Excel. Journal of Chemical Education, 98(2), 495-505. https://doi.org/10.1021/acs.jchemed.0c01016

Powder diffraction is one of the most widely used analytical techniques for characterizing solid state materials. It can be used for phase or polymorph identification, quantitative analysis, cell parameter determination, or even full crystal structur... Read More about Structure Analysis from Powder Diffraction Data: Rietveld Refinement in Excel.

Revisiting the thermal and chemical expansion and stability of La0.6Sr0.4FeO3− (2020)
Journal Article
de Leeuwe, C., Hu, W., Neagu, D., Papaioannou, E. I., Pramana, S., Ray, B., Evans, J. S., & Metcalfe, I. S. (2021). Revisiting the thermal and chemical expansion and stability of La0.6Sr0.4FeO3−. Journal of Solid State Chemistry, 293, Article 121838. https://doi.org/10.1016/j.jssc.2020.121838

The thermal and chemical expansivity of La1-xSrxFeO3-δ (x ​= ​0.4) was measured using in situ powder neutron and synchrotron X-ray diffraction at temperatures between 932 ​K and 1170 ​K and oxygen partial pressures, , between 10−19 ​bar and 0.1 ​bar,... Read More about Revisiting the thermal and chemical expansion and stability of La0.6Sr0.4FeO3−.

Polymorph exploration of bismuth stannate using first-principles phonon mode mapping (2020)
Journal Article
Rahim, W., Skelton, J. M., Savory, C. N., Evans, I. R., Evans, J. S., Walsh, A., & Scanlon, D. O. (2020). Polymorph exploration of bismuth stannate using first-principles phonon mode mapping. Chemical Science, 11(30), 7904-7909. https://doi.org/10.1039/d0sc02995e

Accurately modelling polymorphism in crystalline solids remains a key challenge in computational chemistry. In this work, we apply a theoretically-rigorous phonon mode-mapping approach to understand the polymorphism in the ternary metal oxide Bi2Sn2O... Read More about Polymorph exploration of bismuth stannate using first-principles phonon mode mapping.

Amorphous Mixtures of Ice and C60 Fullerene (2020)
Journal Article
Halukeerthi, S. O., Shephard, J. J., Talewar, S. K., Evans, J. S., Rosu-Finsen, A., & Salzmann, C. G. (2020). Amorphous Mixtures of Ice and C60 Fullerene. The Journal of Physical Chemistry A, 124(24), 5015-5022. https://doi.org/10.1021/acs.jpca.0c03439

Carbon and ice make up a substantial proportion of our Universe. Recent space exploration has shown that these two chemical species often coexist including on comets, asteroids and in the interstellar medium. Here we prepare mixtures of C60 fullerene... Read More about Amorphous Mixtures of Ice and C60 Fullerene.

Oxide Ion and Proton Conductivity in Highly Oxygen-Deficient Cubic Perovskite SrSc0.3Zn0.2Ga0.5O2.4 (2020)
Journal Article
Fuller, C. A., Berrod, Q., Frick, B., Johnson, M. R., Avdeev, M., Evans, J. S. O., & Evans, I. R. (2020). Oxide Ion and Proton Conductivity in Highly Oxygen-Deficient Cubic Perovskite SrSc0.3Zn0.2Ga0.5O2.4. Chemistry of Materials, 32(10), 4347-4357. https://doi.org/10.1021/acs.chemmater.0c01378

A series of Zn-substituted compounds, Sr2Sc1–xZnxGaO5–0.5x, based on the brownmillerite-type oxide ion conductor Sr2ScGaO5 have been synthesized, and a single-phase region has been identified at 0.4 ≤ x < 0.6. The structure and dynamics of Sr2Sc0.6Zn... Read More about Oxide Ion and Proton Conductivity in Highly Oxygen-Deficient Cubic Perovskite SrSc0.3Zn0.2Ga0.5O2.4.