Prof. Dr. rer. nat. Jörg Töpfer
Seit dem Jahre 2000 leite ich an der EAH eine Projektgruppe, die sich mit der Entwicklung funktionskeramischer Materialien beschäftigt. Neben den angestellten Projektmitarbeitern gibt es immer wieder die Möglichkeit für engagierte Studenten als studentische Hilfskräfte mitzuarbeiten.
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Lead-free KNNLT piezoceramic multilayer actuators with Ni electrodes cofired under low oxygen partial pressure
W.M. Alkanj, A. Kynast, M. Töpfer, F. Schubert, J. Töpfer
Open Ceramics 17 (2024) 100508
https://doi.org/10.1016/j.oceram.2023.100508 -
Hexagonal ferrites for self-biasing circulators integrated in LTCC microwave modules
M. Heidenreich, J. Schur, J. Müller, W. Gitzel, A.F. Jacob, J. Töpfer
Mat. Res. Bull. 178 (2024) 112878
https://doi.org/10.1016/j.materresbull.2024.112878 -
Assessment of artificial anisotropic materials for transverse thermoelectric generators
R. Löhnert, A. Bochmann, A. Ibrahim, J. Töpfer
Phys. Status Solidi A (2024) 2400321
https://doi.org/10.1002/pssa.202400321 -
Ontology-based data acquisition, refinement, and utilization in the development of a multilayer ferrite inductor
B. Mieller, S. Ben Hassine, J. Töpfer, C. Priese, A. Bochmann, B. Capraro, S. Stark, U. Partsch, C. Fresemann
Adv. Eng. Mater. (2024) 2401042
https://doi.org/10.1002/adem.202401042
- Thermoanalytic characterization of binder burnout and sintering of lead free piezoelectric KNNLT multilayer laminates with Ni electrodes
M. W. Alkanj, A. Kynast, M. Töpfer, F. Schubert, J. Töpfer
J. Therm. Anal. Calor. (2023)
https://doi.org/10.1007/s10973-022-11844-0 - NiMn2O4 revisited: Temperature-dependent cation distribution from in situ neutron diffraction and thermopower studies
J. Dinger, T. Friedrich, T. Reimann, J. Töpfer
J. Am. Ceram. Soc. 106 (2023) 1834-1847.
https://doi.org/10.1111/jace.18865 - Fabrication of self-biased circulators with integrated hexagonal microwave ferrites using LTCC technology
M. Heidenreich, J. Schur, J. Müller, B. Capraro, W. Gitzel, A.F. Jacob, J. Töpfer, Jörg
Ceramic Forum International cfi/Ber. DKG 100 [2] (2023) E38-E46.
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Synthesis and properties of lead-free BNT-BT-xCZ ceramics as high-temperature dielectrics
T. Schulz, V. Veerapandiyan, M. Deluca, J. Töpfer
Mat. Res. Bull. 145 (2022) 111560.
https://doi.org/10.1016/j.materresbull.2021.111560 -
Large Thermal Expansion LTCC System for Cofiring with Integrated Functional Ceramics Layers
B. Capraro, M. Heidenreich, J. Töpfer
Materials 15 (2022) 564.
https://doi.org/10.3390/ma15020564 -
Sintering and electrical properties of Cu-substituted Zn-Co-Ni-Mn spinel ceramics for NTC thermistors thick films
C. Teichmann, J. Töpfer
J. Europ. Ceram. Soc. 42 (2022) 2261-2267.
https://doi.org/10.1016/j.jeurceramsoc.2021.12.078 -
Tuning of high-temperature dielectric properties in the system (Bi0.5Na0.5)TiO3 –BaTiO3–CaZrO3
T. Schulz, A. Knauer, P. Schaaf, J. Töpfer
Ceram. Intl. 48 (2022) 22187-22195
https://doi.org/10.1016/j.ceramint.2022.04.220 -
The effect of microstructure on the initial permeability of Ni-Zn ferrite
C. Priese, J. Töpfer
J. Magn. Magn. Mater. 560 (2022) 169581.
https://doi.org/10.1016/j.jmmm.2022.169581 -
Enhancing the thermoelectric properties of CaMnO3-d via optimal substituent selection
R. Löhnert, J. Töpfer
J. Solid State Chem. 315 (2022) 123437
https://doi.org/10.1016/j.jssc.2022.123437 -
Oxidation Behavior, Insulation Resistance, and Permeability of FeSiCr Alloys for Multilayer Inductors
C. Priese, J. Töpfer,
Alloys 1 (2022) 288-297.
https://doi.org/10.3390/alloys1030019
- Low pO2 sintering and reoxidation of lead-free KNNLT piezoceramic laminates
T. Reimann, S. Fröhlich, A. Bochmann, A. Kynast, M. Töpfer, E. Hennig, J. Töpfer
J. Europ. Ceramic Soc. 41 (2021) 344-351. - Phase Formation, Microstructure and Permeability of Fe-Deficient NiCu-Zn Ferrites, (I): Effect of Sintering Temperature.
C. Priese, J. Töpfer
Magnetochemistry 7 (2021) 118. https://doi.org/10.3390/magnetochemistry7080118 - Ni‐Cu‐Zn ferrites with high Curie temperature for multilayer inductors with increased operating temperatures
T. Reimann, B. Capraro, H. Bartsch, J. Töpfer
Intl. J. Appl. Ceram. Techn. 18 (2021) 129-137. -
Low-temperature sintered Ni–Zn–Co–Mn–O spinel oxide ceramics for multilayer NTC thermistors
T. Reimann, J. Töpfer
J. Mater. Science: Mat. Electr. 32(8) (2021) 10761-10768.
DOI 10.1007/s10854-021-05733-9 -
Cofiring of LTCC multilayer assemblies with integrated NTC thermistor temperature sensor layers
T. Reimann, S. Barth, B. Capraro, H. Bartsch, J. Töpfer
Ceram. Inter. 47 (2021) 27849-27853.
https://doi.org/10.1016/j.ceramint.2021.06.213
- Multilayer ferrite inductors for the use at higher temperatures
H. Bartsch, S. Thiele, J. Müller, D. Schabbel, B. Capraro, S. Grund, J. Töpfer
Microelectronics Inter. 37 (2020) 73-78. - Phase stability and magnetic properties of SrFe18O27 W-type hexagonal ferrite
T. Reimann, T. Schmidt, J. Töpfer
J. Am. Ceram. Soc. 103 (2020) 324-334. - Ga-, Y-, and Sc-substituted M-type ferrites for self-biasing circulators in LTCC microwave modules
M. Heidenreich, X. Ma, W. Gitzel, A. Jacob, B. Capraro, J. Töpfer
AIP Advances 10 (2020) 025315. - Circuit-Board-Integrated Transformers: Design and Manufacture
R. Matz, T. Rabe, J. Töpfer, S. Ziesche
J. Ceram. Sci. Technol., 11 (2020) 44-61. - Phase formation and saturation magnetization of La-Zn-substituted M-type strontium ferrites
T. Schmidt, D. Seifert, J. Töpfer
J. Magn. Magn. Mater. 508 (2020) 166887 - Hexavalent (Me ‐ W/Mo)‐modified (Ba,Ca)TiO3‐Bi(Mg,Me)O3 perovskites for high‐temperature dielectrics
T. Schulz, V.K. Veerapandiyan, T. Gindel, M. Deluca, J. Töpfer
J. Am. Ceram. Soc. 103 (2020) 6881-6892.
- Sintering, microwave properties, and circulator applications of textured Sc-substituted M-type ferrite thick films
S. Bierlich, T. Reimann, F. Gellersen, A. Jacob, J. Töpfer
J. Europ. Ceram. Soc. 39 (2019) 3077-3081 - Transverse thermoelectric multilayer generator with bismuth-substituted calcium cobaltite: Design optimization through variation of tilt angle
A. Bochmann, T. Reimann, T. Schulz, S. Teichert, J. Töpfer
J. Europ. Ceram. Soc. 39 (2019) 2923-2929 - Synthesis and magnetic properties of hard/soft SrAl2Fe10O19/Fe(FeCo2) nanocomposites
M. Kahnes, J. Töpfer
J. Magn. Magn. Mater. 480 (2019) 40-46 - Phase formation and magnetic properties of CoFe2O4/CoFe2 nanocomposites
M. Kahnes, R. Müller, J. Töpfer
Mater. Chem. Phys. 227 (2019) 83-89 - Phase formation, magnetic properties, and phase stability in reducing atmosphere of M-type strontium hexaferrite nanoparticles synthesized via a modified citrate process
C. Bohlender, M. Kahnes, R. Müller, J. Töpfer
J. Mater. Sci. 54 (2019) 1136-1146
- Low-temperature sintering of BaTiO3 positive temperature coefficient of resistivity (PTCR) ceramics
C. Teichmann, J. Töpfer
J. Mater. Sci.: Mater. Electr. 29 (2018) 17881-17886 - Synthesis, doping and electrical bulk response of (Bi1/2Na1/2)xBa1-xTiO3 + CaO-based ceramics with positive temperature coefficient of resistivity (PTCR)
D. Mächler, R. Schmidt, J. Töpfer
J. Alloys Comp. 762 (2018) 209-215 - Sintering behavior, microstructure and thermoelectric properties of calcium cobaltite thick films for transversal thermoelectric multilayer generators
T. Schulz, T. Reimann, A. Bochmann, A. Vogel, B. Capraro, B. Mieller, S.Teichert, J. Töpfer
J. Europ. Ceram. Soc. 38 (2018) 1600-1607 - Oxide multilayer thermoelectric generators
J. Töpfer, T. Reimann, T. Schulz, A. Bochmann, B. Capraro, S. Barth, A. Vogel, S. Teichert
Intl. J. Appl. Ceram. Techn. DOI: 10.1111/ijac.12822
- Fabrication of a transversal multilayer rhermoelectric generator with substituted calcium manganite
T. Reimann, A. Bochmann, A. Vogel, B. Capraro, S. Teichert, J. Töpfer
J. Am. Ceram. Soc. 100 (2017) 5700-5708 - Fabrication of a transversal multilayer rhermoelectric generator with substituted calcium manganite
T. Reimann, A. Bochmann, A. Vogel, B. Capraro, S. Teichert, J. Töpfer
J. Am. Ceram. Soc. 100 (2017) 5700-5708 - Evaluation of soft chemistry methods to synthesize Gd-doped CaMnO3-sigma with improved thermoelectric properties
R. Löhnert, M. Stelter, J. Töpfer
Mater. Sci. Engin. B223 (2017) 185-193 - Effect of SiO2 sintering additive on the positive temperature coefficient of resistivity (PTCR) behavior of (Bi1/2Na1/2)0.1Ba0.9TiO3 + CaO ceramics
D. Mächler, J. Töpfer
Mater. Res. Bull. 89 (2017) 217-223 - Thermoelectric properties of Gd/W double substituted calcium, manganite
T. Reimann, J. Töpfer
J. Alloys Comp. 699 (2017) 788-795 - Low-temperature sintering and magnetic properties of Sc- and In-substituted M-type hexagonal barium ferrites for microwave applications
S. Bierlich, F. Gellersen, A. Jacob, J. Töpfer
Mater. Res. Bull. 86 (2017) 19-23
- Effect of oxygen partial pressure on co-firing behavior and magnetic properties of LTCC modules with integrated NiCuZn ferrite layers
H. Naghib zadeh, G. Oder, J. Hesse, T. Reimann, J. Töpfer, T. Rabe
J. Electroceramics, (2016) - Integration of High-Frequency M-Type Hexagonal Ferrite Inductors in LTCC Multilayer Modules
S. Bierlich, T. Reimann, J. Töpfer, S. Barth, B. Capraro, H. Bartsch, J. Müller
Intl J. Appl. Ceram. Techn. 13[3] (2016) 540-548 - Electron spin resonance (ESR) of magnetic sublattices in Sc-substituted barium hexaferrite
R. Valenzuela Monjaras, R. Diaz-Pardo, S. Bierlich, J. Töpfer
AIP Advances 6 (2016) 055202 - A monolithic oxide-based transversal thermoelectric energy harvester
S. Teichert, A. Bochmann, T. Reimann, T. Schulz, C. Dressler, S. Udich, J. Töpfer
J. Electron. Mat. 45 (2016) 1966-1969 - Integration of additive-free Ni-Cu-Zn ferrite layers into LTCC multilayer moduless
J. Hesse, H. Naghib-zadeh, T. Rabe, J. Töpfer
J. Europ. Ceram. Soc. 36 (2016) 1931-1937 - Effect of Carbon Nanotubes on Thermoelectric Properties in Zn0.98Al0.02O
C. Dressler, R. Löhnert, J. Gonzales-Julian, O. Guillon, J. Töpfer, S. Teichert
J. Electr. Mater. DOI: 10.1007/s11664-015-4070-4 (2016) - Thermoelectric properties of Ca3Co4O9 ceramics prepared by an alternative pressure-less sintering/annealing method
T. Schulz, J. Töpfer
J. Alloys Comp. 659 (2016) 122-126
- Effect of sintering conditions on microstructure and dielectric properties of CaCu3Ti4O12 (CCTO) ceramics
R. Löhnert, R. Schmidt, J. Töpfer
J. Electroceramics 34 (2015) 241-248 - High-Performance ceramics for power, chemical, machine and plant engineering
B. Voigtsberger, W. Rossner, M. Stelter, J. Töpfer, J. Eichler, I. Voigt, H. Voss
Ceramic Forum International/Ber. DKG 92 (2015) E187-190 - An oxide-based thermoelectric generator: Transversal thermoelectric strip device
S. Teichert, A. Bochmann, T. Reimann, T. Schulz, C. Dressler, J. Töpfer
AIP Advances 5 (2015) 077105 - Charge localization and magnetocrystalline anisotropy in La, Pr, and Nd substituted Sr hexaferrites
V. Chlan, K. Kouril, K. Ulicna, H. Stepankova, J. Töpfer, D. Seifert
Phys. Rev. B 92 (2015) 125125 - Integration of CaCu3Ti4O12 capacitors into LTCC multilayer moduless
R. Löhnert, B. Capraro, S. Barth, H. Bartsch, J. Müller, J. Töpfer
J. Europ. Ceram. Soc. 35 (2015) 3043-3049 - Chemical and structural effects on the high-temperaturemechanical behavior of (1-x)(Na1/2Bi1/2TiO3) xBaTiO3 ceramics
M. Deluca, G. Picht, M. J. Hoffmann, A. Rechtenbach, J. Töpfer, F.H. Schader, K.G. Webber
J. Appl. Phys. 117 (2015) 134110 - A Mössbauer investigation of Sr1-xLaxFe12O19 (0 ≤ x ≤ 1)M-type hexaferrites
J.-M. LeBreton, D. Seifert, J. Töpfer, L. Lechevallier
Physica B 470-471 (2015) 33-38 - Co/Ti-substituted M-type hexagonal ferrites for high-frequency multilayer inductors
S. Bierlich, T. Reimann, H. Bartsch, J. Töpfer
J. Magn. Magn. Mater. 384 (2015) 1-5 - Transversal oxide-metal thermoelectric device for low-power energy harvesting
C. Dressler, A. Bochmann, T. Schulz, T. Reimann, J. Töpfer, S. Teichert
Energy Harv. Systems 2[1] (2015) 25-35 - Hexagonal ferrites of X-, W-, and M-type in the system Sr-Fe-O: a comparative study
J. Töpfer, D. Seifert, J.M. Le Breton, F. Langenhorst, V. Chlan, K. Kouril, H. Stepankova
J. Solid State Chem. 226 (2015) 133-141 - Complex additive systems for Mn-Zn ferrites with low power loss
J. Töpfer, A. Angermann
J. Appl. Phys. 117 (2015) 17A504 - Microstructure and electric properties of CaCu3Ti4O12 multilayer capacitors
R. Löhnert, H. Bartsch, R. Schmidt, B. Capraro, J. Töpfer
J. Am. Ceram. Soc. 98 (2015) 141-147
Projektgruppe Funktionskeramik
Mitarbeiter der Arbeitsgruppe
Sonstiges
Wissenschaftlicher Mitarbeiter
Sonstiges
Wissenschaftlicher Mitarbeiter, Projekt Thermumox
Sonstiges
Laboring. für Chemielabor, Labor f. Werkstoffdiagnostik (Thermoanalyse, Röntgendiffraktometrie), Labor Glas / Keramik
Sprechzeit: Online (nach vorheriger Absprache per E-Mail)
Sonstiges
Wissenschaftlicher Mitarbeiter
Sonstiges
Wissenschaftlicher Mitarbeiter
Sonstiges
Wissenschaftliche Mitarbeiterin
Sonstiges
Wissenschaftlicher Mitarbeiter
Sonstiges
Wissenschaftlicher Mitarbeiter
Sonstiges
Wissenschaftlicher Mitarbeiter
Highlights
Titelblatt vom International Journal of Applied Ceramic Technology
98. DKG-Jahrestagung / 98th DKG Annual Meeting
Ernst-Abbe-Hochschule Jena / Hermsdorf (27. - 30. März 2023)
Arbeitsgebiete
Funktionskeramische Werkstoffe / functional ceramics
Weichferrite / soft ferrites - Mn-Zn Ferrite zur Leistungsübertragung / Mn-Zn power ferrites | Hartferrite / hard ferrites - Sr Ferrite als Permanentmagnete / Sr ferrite permanent magnets |
Piezo-, Ferro-, Dielektrische Werkstoffe / piezo-, ferro-, dielectrics - piezokeramische Werkstoffe (PZT, Blei-freie Materialien) /piezoceramics (PTZ,lead-free materials) | Halbleiterkeramik/semiconducting ceramics - thermoelektrische Oxide/synthesis and characterization of thermoelectric oxides |
Werkstoffchemie / materials chemistry
Festkörperchemie von Oxiden / solid state chemistry of oxides - Leitfähigkeit und magnetische Eigenschaften von Oxiden / charge transport and magnetic properties of oxides | Stöchometrieabweichung und Defektchemie funktionaler Oxide / nonstoichiometry and defect chemistry of functional oxides - thermoanalytische Bestimmung der Stöchometrieabweichung von Oxiden / thermoanalytic characterisation of nonstoichiometry of oxides |
Funktionskeramische Schichten / functional ceramics thick film systems
LTCC-Technologie / low temperature ceramic cofiring - Werkstoffe für Multilagensysteme / materials for multilayer components |