Körfer, Sylvia Maria; Bonkowski, Alexander; Kler, Joe; Hatton, Peter; Uberuaga, Blas Pedro; De Souza, Roger A.
The Sluggish Diffusion of Cations in CeO 2 Probed through Molecular Dynamics and Metadynamics Simulations
Advanced engineering materials, 10, 2201788 (2023)
[DOI: 10.1002/adem.202201788]

Usler, Adrian Leonhard; Kemp, Dennis; Bonkowski, Alexander; De Souza, Roger A.
A general expression for the statistical error in a diffusion coefficient obtained from a solid‐state molecular‐dynamics simulation
Journal of computational chemistry, 10, jcc.27090 (2023)
[DOI: 10.1002/jcc.27090]

De Souza, Roger; Kemp, Dennis.; Wolf, Matthew J.; Ramadan, Amr Hazem Helmy
Caution! Static Supercell Calculations of Defect Migration in Higher Symmetry ABX(3) Perovskite Halides May Be Unreliable: A Case Study of Methylammonium Lead Jodide
The journal of physical chemistry letters, 13, 11363-11368 (2022)
[DOI: 10.1021/acs.jpclett.2c0298411363]

Kler, Joe; Börgers, Jacqueline Marie; De Souza, Roger
Surface Space-Charge Potential and Oxygen Surface Exchange Coefficient of SrTiO3: The Effect of Surface Orientation
Advanced materials interfaces, 2201434 (2022)
[DOI: 10.1002/admi.202201434]

De Souza, Roger; Kemp, Dennis; Wolf, Matthew J.; Ramadan, Amr Hazem Helmy
Caution! Static Supercell Calculations of Defect Migration in Higher Symmetry ABX3 Perovskite Halides May Be Unreliable : A Case Study of Methylammonium Lead Iodide
The journal of physical chemistry letters, 13, 11363-11368 (2022)
[DOI: 10.1021/acs.jpclett.2c02984]

Chiabrera, Francesco M.; Baiutti, Federico; Börgers, Jacqueline Marie; Harrington, George F.; Yedra, Lluís; Liedke, Maciej O.; Kler, Joe; Nandi, Pranjal; Sirvent, Juan de Dios; Santiso, Jose; López-Haro, Miguel; Calvino, José J.; Estradé, Sonia; Butterling, Maik; Wagner, Andreas; Peiró, Francesca; De Souza, Roger; Tarancón, Albert
The impact of Mn nonstoichiometry on the oxygen mass transport properties of La0.8Sr0.2MnyO3±δ thin films
JPhys energy, 4, 044011 (2022)
[DOI: 10.1088/2515-7655/ac98df]

Kler, Joe; De Souza, Roger
Hydration Entropy and Enthalpy of a Perovskite Oxide from Oxygen Tracer Diffusion Experiments
The journal of physical chemistry letters, 13, 4133-4138 (2022)
[DOI: 10.1021/acs.jpclett.2c00970]

Kemp, Dennis; Tarancón, Albert; De Souza, Roger
Recipes for superior ionic conductivities in thin-film ceria-based electrolytes
Physical chemistry, chemical physics : PCCP, 24, 12926-12936 (2022)
[DOI: 10.1039/d2cp01335e]

Belthle, Kendra Solveig; Gries, Ute; Müller, Michael Patrick; Kemp, Dennis; Prakash, Abhinav; Rose, Marc-André; Börgers, Jacqueline M.; Jalan, Bharat; Gunkel, Felix; De Souza, Roger
Quantitative Determination of Native Point‐Defect Concentrations at the ppm Level in Un‐Doped BaSnO$_{3}$ Thin Films
Advanced functional materials, 32, 2113023 (2022)
[DOI: 10.1002/adfm.202113023]

Skinner, Stephen J.; Birss, Viola; Rupp, Jennifer; De Souza, Roger
Introduction to the special issue in honour of Prof. John Kilner’s 75th birthday
Journal of materials chemistry / A, 10, 2149-2151 (2022)
[DOI: 10.1039/D2TA90015G]

Wardenga, Hans F.; Schuldt, Katharina N. S.; Waldow, Stephan Peter; De Souza, Roger; Klein, Andreas
Surface potentials of acceptor- and donor-doped CeO 2 thin films and their relation to oxygen surface exchange
Physical chemistry, chemical physics : PCCP, 24, 1072-1080 (2021)
[DOI: 10.1039/D1CP03776E]

Zurhelle, Alexander Friedrich; Stehling, Wilhelm; Waser, Rainer; De Souza, Roger; Menzel, Stephan
Oxygen Diffusion in Platinum Electrodes : A Molecular Dynamics Study of the Role of Extended Defects
Advanced materials interfaces, 10, 2101257 (2021)
[DOI: 10.1002/admi.202101257]

Robens, Elisabeth; Rauschen, Robert; Kaub, Johannes; Parras, Jana Patricia; Kemp, Dennis; Freeman, Colin L.; De Souza, Roger
Perovskite crystal symmetry and oxygen-ion transport: a molecular-dynamics study of perovskite
Journal of materials chemistry / A, 10, 2388-2397 (2021)
[DOI: 10.1039/D1TA06293J]

Schwab, Christian; Schraknepper, Henning; De Souza, Roger
Oxygen transport in single-crystal LaAlO 3 substrates
Physical review materials, 5, 105001 (2021)
[DOI: 10.1103/PhysRevMaterials.5.105001]

Kemp, Dennis; De Souza, Roger
Nonlinear ion mobility at high electric field strengths in the perovskites SrTiO3 and CH3NH3PbI3
Physical review materials, 5, 105401 (2021)
[DOI: 10.1103/PhysRevMaterials.5.105401]

Hasle, Ida; Waldow, Stephan P.; Gries, Ute N.; De Souza, Roger; Vøllestad, Einar; Haugsrud, Reidar
B-site cation inter-diffusion in yttrium substituted barium zirconate
Journal of materials chemistry / A, 9, 21142-21150 (2021)
[DOI: 10.1039/D1TA02391H]

Börgers, Jacqueline M.; Kler, Joe; Ran, Ke; Larenz, Elizabeth; Weirich, Thomas E.; Dittmann, Regina; De Souza, Roger
Faster Diffusion of Oxygen Along Dislocations in (La,Sr)MnO$_{3+δ}$ Is a Space-Charge Phenomenon
Advanced functional materials, 31, 2105647 (2021)
[DOI: 10.1002/adfm.202105647]

De Souza, Roger
Transport properties of dislocations in SrTiO3 and other perovskites
Current opinion in solid state & materials science, 25, 100923 (2021)
[DOI: 10.1016/j.cossms.2021.100923]

Parras, Jana Patricia; Feldmann, Gereon; De Souza, Roger
Fast grain-boundary diffusion paths in ionic solids : Space-charge layers versus interfacial core
Journal of the American Ceramic Society, 104, 5946-5954 (2021)
[DOI: 10.1111/jace.17905]

Usler, Adrian Leonhard; De Souza, Roger
A Critical Examination of the Mott-Schottky Model of Grain-Boundary Space-Charge Layers in Oxide-Ion Conductors
Journal of the Electrochemical Society : JES, 168, 056504 (2021)
[DOI: 10.1149/1945-7111/abfb37]

Li, Linhao; Kler, Joe; West, Anthony R.; De Souza, Roger; Sinclair, Derek C.
High oxide-ion conductivity in acceptor-doped Bi-based perovskites at modest doping levels
Physical chemistry, chemical physics : PCCP, 23, 11327-11333 (2021)
[DOI: 10.1039/d1cp01120k]

Wollstadt, Stephan; De Souza, Roger; Clemens, Oliver
Kinetic Study of the Interdiffusion of Fluorine and Oxygen in the Perovskite-Type Barium Ferrate System BaFeO2.5-xF2x
The journal of physical chemistry / C, 125, 2287-2298 (2021)
[DOI: 10.1021/acs.jpcc.0c10174]

Guillon, Olivier; De Souza, Roger; Mishra, Tarini Prasad; Rheinheimer, Wolfgang
Electric-field-assisted processing of ceramics : Nonthermal effects and related mechanisms
MRS bulletin, 46, 52-58 (2021)
[DOI: 10.1557/s43577-020-00008-w]

Heelweg, Henrik J.; De Souza, Roger
Metadynamics simulations of strontium-vacancy diffusion in SrTiO 3
Physical review materials, 5, 013804 (2021)
[DOI: 10.1103/PhysRevMaterials.5.013804]

Müller, Michael Patrick; Gunkel, Felix; Hoffmann-Eifert, Susanne; De Souza, Roger
The importance of singly charged oxygen vacancies for electrical conduction in monoclinic HfO2
Journal of applied physics, 129, 025104 (2021)
[DOI: 10.1063/5.0036024]

De Souza, Roger; Mueller, David N.
Electrochemical methods for determining ionic charge in solids
Nature materials, 20, 443-446 (2020)
[DOI: 10.1038/s41563-020-0790-9]

Gries, Ute; Kessel, Markus Franz; Hensling, F. V. E.; Dittmann, R.; Martin, Manfred; De Souza, Roger
Behavior of cation vacancies in single-crystal and in thin-film SrTiO 3 : The importance of strontium vacancies and their defect associates
Physical review materials, 4, 123404 (2020)
[DOI: 10.1103/PhysRevMaterials.4.123404]

Genreith-Schriever, Annalena R.; Parras, Jana Patricia; Heelweg, Henrik; De Souza, Roger
The Intrinsic Structural Resistance of a Grain Boundary to Transverse Ionic Conduction
ChemElectroChem, 7, 4693-4694 (2020)
[DOI: 10.1002/celc.202001357]

Falkenstein, Andreas; De Souza, Roger; Meulenberg, Wilhelm A.; Martin, Manfred
A quantitative analysis of two-fold electrical conductivity relaxation behaviour in mixed proton-oxide-ion-electron conductors upon hydration
Physical chemistry, chemical physics, 22, 25032-25041 (2020)
[DOI: 10.1039/D0CP03264F]

Waldow, Stephan Peter; De Souza, Roger
Is excess faster than deficient? A molecular-dynamics study of oxygen-interstitial and oxygen-vacancy diffusion in CeO2
Journal of Physiks energy, 2, 024001 (2020)
[DOI: 10.1088/2515-7655/ab5cfd]

Heisig, Thomas; Kler, Joe; Du, Hongchu; Bäumer, Christoph; Hensling, Felix V. E.; Glöß, Maria; Moors, Marco; Locatelli, Andrea; Menteş, Tevfik Onur; Genuzio, Francesca; Mayer, Joachim; De Souza, Roger; Dittmann, Regina
Antiphase Boundaries Constitute Fast Cation Diffusion Paths in SrTiO 3 Memristive Devices
Advanced functional materials, 30, 2004118 (2020)
[DOI: 10.1002/adfm.202004118]

Genreith-Schriever, Annalena R.; Parras, Jana Patricia; Heelweg, Henrik J.; De Souza, Roger
The Intrinsic Structural Resistance of a Grain Boundary to Transverse Ionic Conduction
ChemElectroChem, 7, 4718-4723 (2020)
[DOI: 10.1002/celc.202000773]

Waldow, Stephan Peter; Statham, Benjamin J.; Wardenga, Hans F.; Weirich, Thomas E.; Klein, Andreas; De Souza, Roger
Oxygen Surface Exchange and Tracer Diffusion in Differently Oriented Thin Films of Gd-Doped CeO2
ACS applied materials & interfaces, 12, 36768-36777 (2020)
[DOI: 10.1021/acsami.0c09605]

Müller, Michael Patrick; Pingen, Katrin; Hardtdegen, Alexander; Aussen, Stephan; Kindsmueller, Andreas; Hoffmann-Eifert, Susanne; De Souza, Roger
Cation diffusion in polycrystalline thin films of monoclinic HfO 2 deposited by atomic layer deposition
APL materials, 8, 081104 (2020)
[DOI: 10.1063/5.0013965]

Börgers, Jacqueline Marie; De Souza, Roger
The surprisingly high activation barrier for oxygen-vacancy migration in oxygen-excess manganite perovskites
Physical chemistry, chemical physics : PCCP, 22, 14329-14339 (2020)
[DOI: 10.1039/D0CP01281E]

Parras, Jana Patricia; De Souza, Roger
Grain-boundary diffusion of cations in fluorite-type oxides is faster but not always easier
Acta materialia, 195, 383-391 (2020)
[DOI: 10.1016/j.actamat.2020.05.022]

Kaub, Johannes; Kler, Joe; Parker, Stephen C.; De Souza, Roger
The usefulness of molecular-dynamics simulations in clarifying the activation enthalpy of oxygen-vacancy migration in the perovskite oxide BaTiO 3
Physical chemistry, chemical physics, 22, 5413-5417 (2020)
[DOI: 10.1039/C9CP06838D]

Tong, Xiaorui; Mebane, David S.; De Souza, Roger
Analyzing the grain‐boundary resistance of oxide‐ion conducting electrolytes: Poisson‐Cahn vs Poisson‐Boltzmann theories
Journal of the American Ceramic Society, 103, 5-22 (2019)
[DOI: 10.1111/jace.16716]

Parras, Jana Patricia; Cao, Chen; Ma, Zheng; Mücke, Robert; Jin, Lei; Dunin-Borkowski, Rafal E.; Guillon, Olivier; De Souza, Roger
The grain-boundary resistance of CeO2 ceramics : A combined microscopy-spectroscopy-simulation study of a dilute solution
Journal of the American Ceramic Society, 103, 1755-1764 (2019)
[DOI: 10.1111/jace.16843]

De Souza, Roger; Barboni, Denis
Iodide-ion conduction in methylammonium lead iodide perovskite : some extraordinary aspects
Chemical communications : ChemComm, 55, 1108-1111 (2019)
[DOI: 10.1039/C8CC09236B]

Zhu, Jiaxin; Lee, Jung-Woo; Lee, Hyungwoo; Xie, Lin; Pan, Xiaoqing; De Souza, Roger; Eom, Chang-Beom; Nonnenmann, Stephen S.
Probing vacancy behavior across complex oxide heterointerfaces
Science advances, 5, eaau8467 (2019)
[DOI: 10.1126/sciadv.aau8467]

De Souza, Roger; Dickey, E. C.
The effect of space-charge formation on the grain-boundary energy of an ionic solid
Philosophical transactions of the Royal Society of London / A, 377, 20180430 (2019)
[DOI: 10.1098/rsta.2018.0430]

Zhang, Haiwu; De Souza, Roger
Optimising oxygen diffusion in non-cubic, non-dilute perovskite oxides based on BiFeO3
Journal of materials chemistry / A, 7, 25274-25278 (2019)
[DOI: 10.1039/C9TA08980B]

Kwon, Deok‐Hwang; Lee, Shinbuhm; Kang, Chan Soon; Choi, Yong Seok; Kang, Sung Jin; Cho, Hae Lim; Sohn, Woonbae; Jo, Janghyun; Lee, Seung‐Yong; Oh, Kyu Hwan; Noh, Tae Won; De Souza, Roger; Martin, Manfred; Kim, Miyoung
Unraveling the Origin and Mechanism of Nanofilament Formation in Polycrystalline SrTiO3 Resistive Switching Memories
Advanced materials, 31, 1901322 (2019)
[DOI: 10.1002/adma.201901322]

Rheinheimer, Wolfgang; Parras, Jana Patricia; Preusker, Jan-Helmut; De Souza, Roger; Hoffmann, Michael J.
Grain growth in strontium titanate in electric fields : The impact of space-charge on the grain-boundary mobility
Journal of the American Ceramic Society, 102, 3779-3790 (2018)
[DOI: 10.1111/jace.16217]

Hellwig, Maren; Köppen, Martin; Hiller, Albert; Koslowski, Hans; Litnovsky, Andrey; Schmid, Klaus; Schwab, Christian; De Souza, Roger
Impact of Surface Roughness on Ion-Surface Interactions Studied with Energetic Carbon Ions 13C+ on Tungsten Surfaces
Condensed Matter, 4, 29 (2019)
[DOI: 10.3390/condmat4010029]

Waldow, Stephan Peter; Wardenga, Hans; Beschnitt, Stefan; Klein, Andreas; De Souza, Roger
Concentration and Diffusivity of Oxygen Interstitials in Niobia-Doped Ceria
The journal of physical chemistry / C, 123, 6340-6350 (2019)
[DOI: 10.1021/acs.jpcc.8b10613]

Kessel, Markus Franz; De Souza, Roger; Martin, Manfred
Correction: Oxygen diffusion in single crystal barium titanate
Physical chemistry, chemical physics, 20, 29568-29568 (2018)
[DOI: 10.1039/C8CP91913E]

Heisig, Thomas; Bäumer, Christoph; Gries, Ute; Müller, Michael Patrick; La Torre, Camilla; Lübben, Michael; Raab, Nicolas; Du, Hongchu; Menzel, Stephan; Mueller, David N.; Jia, Chun-Lin; Mayer, Joachim; Waser, Rainer; Valov, Ilia; De Souza, Roger; Dittmann, Regina
Oxygen Exchange Processes between Oxide Memristive Devices and Water Molecules
Advanced materials, 30, 1800957 (2018)
[DOI: 10.1002/adma.201800957]

Barboni, Denis; De Souza, Roger
The thermodynamics and kinetics of iodine vacancies in the hybrid perovskite methylammonium lead iodide
Energy & environmental science, 11, 3266-3274 (2018)
[DOI: 10.1039/C8EE01697F]