Publications

Toward quantitative thermoelectric characterization of (nano)materials by in-situ transmission electron microscopy
Hettler, S.; Furqan, M.; Sotelo, A.; Arenal, R.
2025. Ultramicroscopy, 268, Art.Nr: 114071. doi:10.1016/j.ultramic.2024.114071

Phase Stability and Structural Evolution of Core/Shell Iron Oxide Nanoparticles Due to Oxidative Diffusion: Implications for Spintronic Applications
Nuñez, J. M.; Lima, E., Jr.; Lohr, J. H.; Vásquez Mansilla, M.; Zysler, R. D.; Tolley, A.; Bartolomé, F.; Rubín, J.; Hettler, S.; Arenal, R.; Aguirre, M. H.; Winkler, E. L.
2025. ACS Applied Nano Materials, 8 (25), 13024–13036. doi:10.1021/acsanm.5c01929

Chemistry and Interfacial Structure Promoting Quasi-van der Waals Epitaxial Growth of WS Nanosheets on Sapphire for Prospective Application in Field-Effect Transistors
Majumder, S.; Shinde, N.; Cavin, J.; Chen, C.; Dey, A. B.; Narayanachari, K. V. L. V.; Zhang, J.; Garcia-Wetten, D.; Dieguez, O.; Hettler, S.; Cohen, A.; Keane, D. T.; Arenal, R.; Rondinelli, J. M.; Ismach, A.; Bedzyk, M. J.
2025. ACS Applied Nano Materials, 8 (18), 9256–9267. doi:10.1021/acsanm.5c00681

Effect of Shell Thickness on the Oxygen Evolution Activity of Core@shell FeO@CoFeO Nanoparticles
Makarchuk, I.; Rotonnelli, B.; Royer, L.; Hettler, S.; Gallet, J.-J.; Bournel, F.; Guehl, J.; Brige, A.; Zitolo, A.; Kéranguéven, G.; Bonnefont, A.; Arenal, R.; Savinova, E.; Asset, T.; Pichon, B. P.
2025. Chemistry of Materials, 37 (3), 833–844. doi:10.1021/acs.chemmater.4c01784

Direct Visualization of Temperature‐Induced Phase Separation of Completely Miscible Au─Pd Alloy by In Situ TEM
Roy, A.; Hettler, S.; Arenal, R.
2025. Small, 21 (19). doi:10.1002/smll.202408109

Vanadium incorporation in ferrite nanoparticles serves as an electron buffer and anisotropy tuner in catalytic and hyperthermia applications
Torres, T. E.; Valdés, D. P.; Hettler, S.; Nuñez, J. M.; Rodrigo, I.; Orue, I.; García, J. Á.; Plazaola, F.; Zysler, R. D.; Lima, E.; Aguirre, M. H.; Goya, G. F.; Arenal, R.
2025. Nanoscale, 17 (16), 10205–10218. doi:10.1039/d4nr04219k

Proximity‐Mediated Multi‐Ferroelectric Coupling in Highly Strained EuO‐Graphene Heterostructures
Pandey, S.; Pin, T.; Hettler, S.; Arenal, R.; Bouillet, C.; Maroutian, T.; Robert, J.; Gobaut, B.; Kundys, B.; Dayen, J.-F.; Halley, D.
2025. Advanced Materials, 37 (17). doi:10.1002/adma.202417669

Synthesis and dynamics of PtSi nanoparticles on a carbon nanofilm by in-situ TEM Joule heating
Hettler, S.; Arenal, R.
2024. Carbon Trends, 15, Art.Nr: 100348. doi:10.1016/j.cartre.2024.100348

Support‐Based Transfer and Contacting of Individual Nanomaterials for In Situ Nanoscale Investigations
Hettler, S.; Furqan, M.; Arenal, R.
2024. Small Methods, 8 (12). doi:10.1002/smtd.202400034

Stable CoO Nanoscrolls with Outstanding Electrical Properties
Hettler, S.; Roy, K. S.; Arenal, R.; Panchakarla, L. S.
2024. Advanced Materials Interfaces, 11 (31). doi:10.1002/admi.202400317

Chemically‐Linked Heterostructures of Palladium Nanosheets and 2H‐MoS
Quirós-Ovies, R.; Bastante, P.; Hettler, S.; Vega-Mayoral, V.; Aina, S.; Balos, V.; Pucher, T.; Castellanos-Gomez, A.; Arenal, R.; Cabanillas-Gonzalez, J.; Pérez, E. M.; Santamaría, J.; Sebastian, V.
2024. Small. doi:10.1002/smll.202406030

Misfit Layered Compounds: Insights into Chemical, Kinetic, and Thermodynamic Stability of Nanophases
Khadiev, A.; Sreedhara, M. B.; Hettler, S.; Novikov, D.; Arenal, R.; Tenne, R.
2024. Accounts of Chemical Research, 57 (22), 3243–3253. doi:10.1021/acs.accounts.4c00412

Nanotubes from Lanthanide-Based Misfit-Layered Compounds: Understanding the Growth, Thermodynamic, and Kinetic Stability Limits
Sreedhara, M. B.; Khadiev, A.; Zheng, K.; Hettler, S.; Serra, M.; Castelli, I. E.; Arenal, R.; Novikov, D.; Tenne, R.
2024. Chemistry of Materials, 36 (9), 4736–4749. doi:10.1021/acs.chemmater.4c00481

Room-temperature anomalous Hall effect in graphene in interfacial magnetic proximity to EuO grown by topotactic reduction
Pandey, S.; Hettler, S.; Arenal, R.; Bouillet, C.; Moghe, A. R.; Berciaud, S.; Robert, J.; Dayen, J.-F.; Halley, D.
2023. Physical Review B, 108 (14), Art.Nr: 144423. doi:10.1103/physrevb.108.144423

Core–shell FeO@CoFeO nanoparticles as high-performance anode catalysts for enhanced oxygen evolution reaction
Royer, L.; Makarchuk, I.; Hettler, S.; Arenal, R.; Asset, T.; Rotonnelli, B.; Bonnefont, A.; Savinova, E.; Pichon, B. P.
2023. Sustainable Energy & Fuels, 7 (14), 3239–3243. doi:10.1039/d3se00130j

Tungsten Oxide Mediated Quasi-van der Waals Epitaxy of WS on Sapphire
Cohen, A.; Mohapatra, P. K.; Hettler, S.; Patsha, A.; Narayanachari, K. V. L. V.; Shekhter, P.; Cavin, J.; Rondinelli, J. M.; Bedzyk, M.; Dieguez, O.; Arenal, R.; Ismach, A.
2023. ACS Nano, 17 (6), 5399–5411. doi:10.1021/acsnano.2c09754

Cooperative Redox Transitions Drive Electrocatalysis of the Oxygen Evolution Reaction on Cobalt–Iron Core–Shell Nanoparticles
Royer, L.; Bonnefont, A.; Asset, T.; Rotonnelli, B.; Velasco-Vélez, J.-J.; Holdcroft, S.; Hettler, S.; Arenal, R.; Pichon, B.; Savinova, E.
2023. ACS Catalysis, 13 (1), 280–286. doi:10.1021/acscatal.2c04512

Ti‐Modified Imogolite Nanotubes as Promising Photocatalyst 1D Nanostructures for H Production
Jimenéz-Calvo, P.; Naciri, Y.; Sobolewska, A.; Isaacs, M.; Zhang, Y.; Leforestier, A.; Degrouard, J.; Rouzière, S.; Goldmann, C.; Vantelon, D.; Hettler, S.; Zaluzec, N. J.; Arenal, R.; Launois, P.; Ghazzal, M. N.; Paineau, E.
2024. Small Methods, 8 (8). doi:10.1002/smtd.202301369

Aberration-corrected transmission electron microscopy with Zernike phase plates
Hettler, S.; Arenal, R.
2022. Ultramicroscopy, 239, Art.Nr: 113564. doi:10.1016/j.ultramic.2022.113564

Strontium-deficient SrCoO–CoO nanotubes as a high ampacity and high conductivity material
Roy, K. S.; Hettler, S.; Arenal, R.; Panchakarla, L. S.
2022. Materials Horizons, 9 (8), 2115–2127. doi:10.1039/d1mh01987b

Catalysts for the hydrogen evolution reaction in alkaline medium: Configuring a cooperative mechanism at the Ag-AgS-MoS interface
Bar-Hen, A.; Hettler, S.; Ramasubramaniam, A.; Arenal, R.; Bar-Ziv, R.; Bar Sadan, M.
2022. Journal of Energy Chemistry, 74, 481–488. doi:10.1016/j.jechem.2022.07.020

Onion-like FeO/MgO/CoFeO magnetic nanoparticles: new ways to control magnetic coupling between soft and hard magnetic phases
Nuñez, J. M.; Hettler, S.; Lima Jr, E.; Goya, G. F.; Arenal, R.; Zysler, R. D.; Aguirre, M. H.; Winkler, E. L.
2022. Journal of Materials Chemistry C, 10 (41), 15339–15352. doi:10.1039/d2tc03144b

Nanotubes from Ternary WSSe Alloys: Stoichiometry Modulated Tunable Optical Properties
Sreedhara, M. B.; Miroshnikov, Y.; Zheng, K.; Houben, L.; Hettler, S.; Arenal, R.; Pinkas, I.; Sinha, S. S.; Castelli, I. E.; Tenne, R.
2022. Journal of the American Chemical Society, 144 (23), 10530–10542. doi:10.1021/jacs.2c03187

Comparative image simulations for phase-plate transmission electron microscopy
Hettler, S.; Arenal, R.
2021. Ultramicroscopy, 227, Art.Nr: 113319. doi:10.1016/j.ultramic.2021.113319

In-situ reduction by Joule heating and measurement of electrical conductivity of graphene oxide in a transmission electron microscope
Hettler, S.; Sebastian, D.; Pelaez-Fernandez, M.; Benito, A. M.; Maser, W. K.; Arenal, R.
2021. 2D Materials, 8 (3), Art.Nr: 031001. doi:10.1088/2053-1583/abedc9

Asymmetric misfit nanotubes: Chemical affinity outwits the entropy at high-temperature solid-state reactions
Sreedhara, M. B.; Hettler, S.; Kaplan-Ashiri, I.; Rechav, K.; Feldman, Y.; Enyashin, A.; Houben, L.; Arenal, R.; Tenne, R.
2021. Proceedings of the National Academy of Sciences, 118 (35), Art.Nr: e2109945118. doi:10.1073/pnas.2109945118

Shelling with MoS: Functional CuS@MoS hybrids as electrocatalysts for the oxygen reduction and hydrogen evolution reactions
Bar-Hen, A.; Bar-Ziv, R.; Ohaion-Raz, T.; Mizrahi, A.; Hettler, S.; Arenal, R.; Bar Sadan, M.
2021. Chemical Engineering Journal, 420, Art.Nr: 129771. doi:10.1016/j.cej.2021.129771

A Detailed Investigation of the Onion Structure of Exchanged Coupled Magnetic FeO@CoFeO@FeO Nanoparticles
Sartori, K.; Musat, A.; Choueikani, F.; Grenèche, J.-M.; Hettler, S.; Bencok, P.; Begin-Colin, S.; Steadman, P.; Arenal, R.; Pichon, B. P.
2021. ACS Applied Materials & Interfaces, 13 (14), 16784–16800. doi:10.1021/acsami.0c18310

Phase plates in the transmission electron microscope: operating principles and applications
Malac, M.; Hettler, S.; Hayashida, M.; Kano, E.; Egerton, R. F.; Beleggia, M.
2021. Microscopy, 70 (1), 75–115. doi:10.1093/jmicro/dfaa070

YS-TaS and YLaS-TaS (0 ≤ x ≤ 1) Nanotubes: A Family of Misfit Layered Compounds
Hettler, S.; Sreedhara, M. B.; Serra, M.; Sinha, S. S.; Popovitz-Biro, R.; Pinkas, I.; Enyashin, A. N.; Tenne, R.; Arenal, R.
2020. ACS Nano, 14 (5), 5445–5458. doi:10.1021/acsnano.9b09284

Unraveling the Decomposition Pathways of LaS-TaS Misfit-Layered Compound Nanostructures under Extreme Electrical Currents by In Situ TEM
Hettler, S.; Sreedhara, M. B.; Tenne, R.; Arenal, R.
2025. The Journal of Physical Chemistry C, 129 (30), 13803–13812. doi:10.1021/acs.jpcc.5c03498

Understanding the effect of CeCo-coated metallic interconnectors on the structure and chemistry of LSCF-GDC composite air electrodes using transmission electron microscopy
Makvandi, A.; Grosselindemann, C.; Hettler, S.; Strömer, H.; Weber, A.; Eggeler, Y.
2025. 19th International Symposium on Solid Oxide Fuel Cells (SOFC 2025), Stockholm, Schweden, 13.–18. Juli 2025

On the relationship between oxygen K edge fine structure and cobalt/nickel content in magnetite-based core-shell nanoparticles
Hettler, S.; Arenal, R.
2025. Micron, 196-197, 103858. doi:10.1016/j.micron.2025.103858

Structure and properties of tubular structures based on the quaternary misfit layered compound SmYS–TaS
Hettler, S.; Furqan, M.; Sreedhara, M. B.; Khadiev, A.; Tenne, R.; Arenal, R.
2025. RSC Advances, 15 (13), 9605 – 9617. doi:10.1039/D5RA00780A

Carbon‐film‐based Zernike phase plates with smooth thickness gradient for phase‐contrast transmission electron microscopy with reduced fringing artefacts
Obermair, M.; Hettler, S.; Dries, M.; Hugenschmidt, M.; Spiecker, R.; Gerthsen, D.
2022. Journal of Microscopy, 287 (1), 45–58. doi:10.1111/jmi.13108

Analyzing contrast in cryo-transmission electron microscopy: Comparison of electrostatic Zach phase plates and hole-free phase plates
Obermair, M.; Hettler, S.; Hsieh, C.; Dries, M.; Marko, M.; Gerthsen, D.
2020. Ultramicroscopy, 218, Art.-Nr.: 113086. doi:10.1016/j.ultramic.2020.113086

Phase masks for electron microscopy fabricated by thermal scanning probe lithography
Hettler, S.; Radtke, L.; Grünewald, L.; Lisunova, Y.; Peric, O.; Brugger, J.; Bonanni, S.
2019. Micron, 127, Art.-Nr.: 102753. doi:10.1016/j.micron.2019.102753

Fabrication of phase masks from amorphous carbon thin films for electron-beam shaping
Grünewald, L.; Gerthsen, D.; Hettler, S.
2019. Beilstein journal of nanotechnology, 10, 1290–1302. doi:10.3762/bjnano.10.128

Investigation of hole-free phase plate performance in transmission electron microscopy under different operation conditions by experiments and simulations
Pretzsch, R.; Dries, M.; Hettler, S.; Spiecker, M.; Obermair, M.; Gerthsen, D.
2019. Advanced structural and chemical imaging, 5 (1), Art.Nr. 5. doi:10.1186/s40679-019-0067-z

Quasi non-diffractive electron Bessel beams using direct phase masks with applications in electron microscopy
Hettler, S.; Grünewald, L.; Malac, M.
2019. New journal of physics, 21, Article no: 033007. doi:10.1088/1367-2630/ab03da

Charging of electron beam irradiated amorphous carbon thin films at liquid nitrogen temperature
Hettler, S.; Onoda, J.; Wolkow, R.; Pitters, J.; Malac, M.
2019. Ultramicroscopy, 196, 161–166. doi:10.1016/j.ultramic.2018.10.010

Charging of carbon thin films in scanning and phase-plate transmission electron microscopy
Hettler, S.; Kano, E.; Dries, M.; Gerthsen, D.; Pfaffmann, L.; Bruns, M.; Beleggia, M.; Malac, M.
2018. Ultramicroscopy, 184, 252–266. doi:10.1016/j.ultramic.2017.09.009

Oxide-free aC/Zr0.65 Al0.075 Cu0.275/aC phase plates for transmission electron microscopy
Dries, M.; Obermair, M.; Hettler, S.; Hermann, P.; Seemann, K.; Seifried, F.; Ulrich, S.; Fischer, R.; Gerthsen, D.
2018. Ultramicroscopy, 189, 39–45. doi:10.1016/j.ultramic.2018.03.003

Thin-film phase plates for transmission electron microscopy fabricated from metallic glass alloys
Dries, M.; Obermair, M.; Hettler, S.; Hermann, P.; Seemann, K.; Seifried, F.; Ulrich, S.; Gerthsen, D.
2017. Microscopy Conference 2017, Lausanne, CH, August 21-25, 2017. Proceedings published online, 754–755, SwissTech Convention Center

Thin-film phase plates for transmission electron microscopy fabricated from metallic glass alloys
Dries, M.; Obermair, M.; Hettler, S.; Hermann, P.; Seemann, K.; Seifried, F.; Ulrich, S.; Gerthsen, D.
2017. Microscopy Conference 2017, Lausanne, CH, August 21-25, 2017

Computer simulations analysis for determining the polarity of charge generated by high energy electron irradiation of a thin film
Malac, M.; Hettler, S.; Hayashida, M.; Kawasaki, M.; Konyuba, Y.; Okura, Y.; Iijima, H.; Ishikawa, I.; Beleggia, M.
2017. Micron, 100, 10–22. doi:10.1016/j.micron.2017.03.015

Contrast of Backscattered Electron SEM Images of Nanoparticles on Substrates with Complex Structure
Kowoll, T.; Müller, E.; Fritsch-Decker, S.; Hettler, S.; Störmer, H.; Weiss, C.; Gerthsen, D.
2017. Scanning, 2017, Article ID 4907457. doi:10.1155/2017/4907457

Carbon contamination in scanning transmission electron microscopy and its impact on phase-plate applications
Hettler, S.; Dries, M.; Hermann, P.; Obermair, M.; Gerthsen, D.; Malac, M.
2017. Micron, 96, 38–47. doi:10.1016/j.micron.2017.02.002

Electrostatic Zach phase plates: optimization of properties and applications
Gerthsen, D.; Hettler, S.; Dries, M.; Gamm, B.; Schultheiss, K.; Frindt, N.; Schröder, R.; Zach, J.
2012. Microscopy and microanalysis / Supplement, 18 (2), 466–467. doi:10.1017/S1431927612004187

Thin-Film Phase Plates for Transmission Electron Microscopy Fabricated from Metallic Glasses
Dries, M.; Hettler, S.; Schulze, T.; Send, W.; Müller, E.; Schneider, R.; Gerthsen, D.; Luo, Y.; Samwer, K.
2016. Microscopy and microanalysis, 22 (5), 955–963. doi:10.1017/S143192761601165X

High-resolution transmission electron microscopy with an electrostatic Zach phase plate
Hettler, S.; Dries, M.; Zeelen, J.; Oster, M.; Schröder, R. R.; Gerthsen, D.
2016. New journal of physics, 18 (5), Art.Nr.: 053005. doi:10.1088/1367-2630/18/5/053005

Low affinity binding of plasma proteins to lipid-coated quantum dots as observed by in situ fluorescence correlation spectroscopy
Klapper, Y.; Maffre, P.; Shang, L.; Nilsson-Ekdahl, K.; Nilsson, B.; Hettler, S.; Dries, M.; Gerthsen, D.; Nienhaus, G. U.
2015. Nanoscale, 7 (22), 9980–9984. doi:10.1039/c5nr01694k

On the role of inelastic scattering in phase-plate transmission electron microscopy
Hettler, S.; Wagner, J.; Dries, M.; Oster, M.; Wacker, C.; Schröder, R. R.; Gerthsen, D.
2015. Ultramicroscopy, 155, 27–41. doi:10.1016/j.ultramic.2015.04.001

Transmissionselektronenmikroskopie mit elektrostatischen Zach-Phasenplatten. Dissertation
Hettler, S. J.
2015. Karlsruher Institut für Technologie (KIT). doi:10.5445/IR/1000047637

In-focus electrostatic zach phase plate imaging for transmission electron microscopy with tunable phase contrast of frozen hydrated biological samples
Frindt, N.; Oster, M.; Hettler, S.; Gamm, B.; Dieterle, L.; Kowalsky, W.; Gerthsen, D.; Schröder, R. R.
2014. Microscopy and Microanalysis, 20 (1), 175–183. doi:10.1017/S1431927613013901

A nanocrystalline Hilbert phase-plate for phase-contrast transmission electron microscopy
Dries, M.; Hettler, S.; Gamm, B.; Müller, E.; Send, W.; Müller, K.; Rosenauer, A.; Gerthsen, D.
2014. Ultramicroscopy, 139, 29–37. doi:10.1016/j.ultramic.2014.01.002

Improving fabrication and application of zach phase plates for phase-contrast transmission electron microscopy
Hettler, S.; Gamm, B.; Dries, M.; Frindt, N.; Schröder, R. R.; Gerthsen, D.
2012. Microscopy and Microanalysis, 18 (5), 1010–1015. doi:10.1017/S1431927612001560

Zach phase plate imaging for transmission electron microscopy of macromolecular complexes
Frindt, N.; Gamm, B.; Hettler, S.; Oster, M.; Wacker, I.; Gerthsen, D.; Schröder, R. R.
2011. Microscopy Conf.2011 (MC 2011), Kiel, August 28 - September 2, 2011