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1

Barboux, P. "Protonic conductivity in hydrates." Solid State Ionics 27, no. 4 (1988): 221–25. http://dx.doi.org/10.1016/0167-2738(88)90213-5.

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2

Merkle, Rotraut, Maximilian F. Hoedl, Giulia Raimondi, Reihaneh Zohourian, and Joachim Maier. "Oxides with Mixed Protonic and Electronic Conductivity." Annual Review of Materials Research 51, no. 1 (2021): 461–93. http://dx.doi.org/10.1146/annurev-matsci-091819-010219.

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Oxides with mixed protonic and p-type electronic conductivity (and typically containing also mobile oxygen vacancies) are important functional materials, e.g., for oxygen electrodes in protonic ceramic electrochemical cells or for permeation membranes. Owing to the presence of three carriers, their defect chemical behavior is complex. Deviations from ideal behavior (defect interactions) have to be taken into account, which are related to the partially covalent character of the transition metal–oxygen bonds. Compared to acceptor-doped Ba(Zr,Ce)O3− z electrolytes, perovskites with redox-active t
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3

Salman, Fathy Esmail, Bozena Hilczer, and Czeslaw Pawlaczyk. "Protonic Conductivity inLi(N2H5)SO4Single Crystals." Japanese Journal of Applied Physics 24, S2 (1985): 668. http://dx.doi.org/10.7567/jjaps.24s2.668.

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4

Larring, Y. "Protonic conductivity in Ca-doped yttria." Solid State Ionics 49 (December 1991): 73–77. http://dx.doi.org/10.1016/0167-2738(91)90070-r.

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5

Kosacki, I. "Mixed conductivity in SrCe0.95Yb0.05O3 protonic conductors." Solid State Ionics 80, no. 3-4 (1995): 223–29. http://dx.doi.org/10.1016/0167-2738(95)00142-s.

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6

Mäki-Ontto, R., K. de Moel, E. Polushkin, G. Alberda van Ekenstein, G. ten Brinke, and O. Ikkala. "Tridirectional Protonic Conductivity in Soft Materials." Advanced Materials 14, no. 5 (2002): 357. http://dx.doi.org/10.1002/1521-4095(20020304)14:5<357::aid-adma357>3.0.co;2-q.

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7

Javadi, H. H. S., F. Zuo, M. Angelopoulos, A. G. Macdiarmid, and A. J. Epstein. "Frequency Dependent Conductivity of Emeraldine: Absence of Protonic Conductivity." Molecular Crystals and Liquid Crystals Incorporating Nonlinear Optics 160, no. 1 (1988): 225–33. http://dx.doi.org/10.1080/15421408808083017.

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8

Shikama, Tatsuo, Bun Tsuchiya, Shinji Nagata, and Kentaro Toh. "Electrical Conductivity of Proton Conductive Ceramics under Reactor Irradiation." Advances in Science and Technology 45 (October 2006): 1974–79. http://dx.doi.org/10.4028/www.scientific.net/ast.45.1974.

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Electrical charges may be transported in ceramics by not only electrons but also by electron-holes, ions, and protons. Especially in nuclear fusion environments, electrical conductivity by proton migration (protonic conduction) will play an important role, as supply of hydrogen isotopes is sufficient and working temperature for ceramics will be in general high. In the present paper, radiation effects on the electrical conductivity of perovskite-type oxides will be reviewed, emphasizing radiation effects on transport behaviors of hydrogen and on reducing behaviors of oxide ceramics. Some perovs
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9

Bukun, N. "Protonic conductivity of novel composite superionic conductors." Solid State Ionics 136-137, no. 1-2 (2000): 279–84. http://dx.doi.org/10.1016/s0167-2738(00)00325-8.

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10

Vakulenko, A. "Protonic conductivity of neutral and acidic silicotungstates." Solid State Ionics 136-137, no. 1-2 (2000): 285–90. http://dx.doi.org/10.1016/s0167-2738(00)00404-5.

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11

Klauer, S., M. Wöhlecke, and S. Kapphan. "Isotope effect of protonic conductivity in LiNbO3." Radiation Effects and Defects in Solids 119-121, no. 2 (1991): 699–704. http://dx.doi.org/10.1080/10420159108220805.

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12

de Oliveira, A. L., O. de O. Damasceno, J. de Oliveira, and E. J. L. Schouler. "Complex impedance study of KDP protonic conductivity." Materials Research Bulletin 21, no. 7 (1986): 877–85. http://dx.doi.org/10.1016/0025-5408(86)90174-1.

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13

Peng, Zhenzhen, Ruisong Guo, Ziguang Yin, and Juan Li. "BaZr0.9Y0.1O2.95/Na2SO4 composite with enhanced protonic conductivity." Journal of Wuhan University of Technology-Mater. Sci. Ed. 24, no. 2 (2009): 269–72. http://dx.doi.org/10.1007/s11595-009-2269-z.

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14

Wu, Xuefei, and Qingyin Wu. "Synthesis and high proton conductivity of an indium-substituted Keggin-type quaternary heteropoly acid." Dalton Transactions 50, no. 20 (2021): 6793–96. http://dx.doi.org/10.1039/d1dt00966d.

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An indium-substituted Keggin quaternary heteropoly acid, H<sub>4</sub>[In(H<sub>2</sub>O)PW<sub>9</sub>Mo<sub>2</sub>O<sub>39</sub>]·11H<sub>2</sub>O, is reported. It owes high protonic conductivity as 2.32 ×10<sup>−4</sup> S cm<sup>−1</sup>, with 35.52 kJ mol<sup>−1</sup> as the activation energy, implying a potential solid protonic conductor.
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15

Guo, Liqiang, Juan Wen, Guanggui Cheng, Ningyi Yuan, and Jianning Ding. "Synaptic behaviors mimicked in indium-zinc-oxide transistors gated by high-proton-conducting graphene oxide-based composite solid electrolytes." Journal of Materials Chemistry C 4, no. 41 (2016): 9762–70. http://dx.doi.org/10.1039/c6tc02228f.

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16

Poinsignon, C. "Protonic conductivity and water dynamics in swelling clays." Solid State Ionics 97, no. 1-4 (1997): 399–407. http://dx.doi.org/10.1016/s0167-2738(97)00020-9.

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17

CANADAY, J., S. CHEHAB, A. KURIAKOSE, A. AHMAD, and T. WHEAT. "Protonic conductivity of HyceramTM, a bonded hydronium NASICON." Solid State Ionics 48, no. 1-2 (1991): 113–21. http://dx.doi.org/10.1016/0167-2738(91)90206-q.

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18

PNEVMATIKOS, S. N., and G. P. TSIRONIS. "PROTONIC CONDUCTIVITY : A NEW APPLICATION OF SOLITON THEORY." Le Journal de Physique Colloques 50, no. C3 (1989): C3–3—C3–10. http://dx.doi.org/10.1051/jphyscol:1989301.

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19

Dolinšek, J., M. Karayanni, and G. Papavassiliou. "Protonic conductivity in KH2PO4 family studied by NMR." Solid State Ionics 125, no. 1-4 (1999): 159–62. http://dx.doi.org/10.1016/s0167-2738(99)00170-8.

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20

Ordinario, David D., Long Phan, Ward G. Walkup IV, et al. "Bulk protonic conductivity in a cephalopod structural protein." Nature Chemistry 6, no. 7 (2014): 596–602. http://dx.doi.org/10.1038/nchem.1960.

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21

Dippel, Th, N. Hainovsky, K. D. Kreuer, W. Munch, and J. Maier. "Hydrogen bonding, lattice dynamics and fast protonic conductivity." Ferroelectrics 167, no. 1 (1995): 59–66. http://dx.doi.org/10.1080/00150199508007720.

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22

Sergienko, A. I. "Dynamics of Bjerrum Faults and Protonic Ice Conductivity." physica status solidi (b) 144, no. 2 (1987): 471–75. http://dx.doi.org/10.1002/pssb.2221440204.

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23

Zaretskii, A. V., V. F. Petrenko, and V. A. Chesnakov. "The protonic conductivity of heavily KOH-doped ice." Physica Status Solidi (a) 109, no. 2 (1988): 373–81. http://dx.doi.org/10.1002/pssa.2211090202.

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24

Deng, Yingxin, Brett A. Helms, and Marco Rolandi. "Synthesis of pyridine chitosan and its protonic conductivity." Journal of Polymer Science Part A: Polymer Chemistry 53, no. 2 (2014): 211–14. http://dx.doi.org/10.1002/pola.27430.

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25

Ivanov, Yu N., A. A. Sukhovsky, I. P. Aleksandrova, J. Totz, and D. Michel. "Mechanism of protonic conductivity in an NH4HSeO4 crystal." Physics of the Solid State 44, no. 6 (2002): 1077–84. http://dx.doi.org/10.1134/1.1485011.

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26

Barbosa, Paula, Nataly C. Rosero-Navarro, Fa-Nian Shi, and Filipe M. L. Figueiredo. "Protonic Conductivity of Nanocrystalline Zeolitic Imidazolate Framework 8." Electrochimica Acta 153 (January 2015): 19–27. http://dx.doi.org/10.1016/j.electacta.2014.11.093.

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27

Zaretskii, A. "High protonic conductivity of heavily KOH-doped ice." Solid State Ionics 36, no. 3-4 (1989): 225–26. http://dx.doi.org/10.1016/0167-2738(89)90177-x.

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28

Garanin, Evgeny M., Yuriy V. Tolmachev, Scott D. Bunge, et al. "Fast protonic conductivity in crystalline benzenehexasulfonic acid hydrates." Journal of Solid State Electrochemistry 15, no. 3 (2010): 549–60. http://dx.doi.org/10.1007/s10008-010-1094-9.

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29

Yugami, Hiroo, Hisashi Kato, and Fumitada Iguchi. "Protonic SOFCs Using Perovskite-Type Conductors." Advances in Science and Technology 95 (October 2014): 66–71. http://dx.doi.org/10.4028/www.scientific.net/ast.95.66.

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High temperature solid oxide fuel cells (SOFCs) have high efficiency and low emissions and contribute to the saving of the fossil fuel and the decreasing of the CO2 emission bringing about the global warning. As concerned about the development of electrolytes, oxide-ion conductors alternative to yttria-stabilized zirconia (YSZ) such as doped CeO2, Sc-SZ and perovskite-type oxides (LaGaO3) etc. have been reported to apply to the intermediate temperature SOFCs (IT-SOFCs).Some of perovskite-type oxides shows high proton conductivity at high temperature and are expected to the electrolyte material
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30

Kee, Benjamin L., David Curran, Huayang Zhu, et al. "Thermodynamic Insights for Electrochemical Hydrogen Compression with Proton-Conducting Membranes." Membranes 9, no. 7 (2019): 77. http://dx.doi.org/10.3390/membranes9070077.

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Membrane electrode assemblies (MEA) based on proton-conducting electrolyte membranes offer opportunities for the electrochemical compression of hydrogen. Mechanical hydrogen compression, which is more-mature technology, can suffer from low reliability, noise, and maintenance costs. Proton-conducting electrolyte membranes may be polymers (e.g., Nafion) or protonic-ceramics (e.g., yttrium-doped barium zirconates). Using a thermodynamics-based analysis, the paper explores technology implications for these two membrane types. The operating temperature has a dominant influence on the technology, wi
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31

Celik, Erdogan, Rajendra S. Negi, Michele Bastianello, et al. "Tailoring the protonic conductivity of porous yttria-stabilized zirconia thin films by surface modification." Physical Chemistry Chemical Physics 22, no. 20 (2020): 11519–28. http://dx.doi.org/10.1039/d0cp01619e.

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32

Aliouane, N. "Investigation of hydration and protonic conductivity of H-montmorillonite." Solid State Ionics 148, no. 1-2 (2002): 103–10. http://dx.doi.org/10.1016/s0167-2738(02)00049-8.

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33

COLOMBAN, P., and J. BADOT. "Frequency dependent conductivity and microwave relaxations in protonic conductors." Solid State Ionics 61, no. 1-3 (1993): 55–62. http://dx.doi.org/10.1016/0167-2738(93)90334-y.

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34

Mangamma, G. "Protonic conductivity of layered HNbWO6 · 1.5H2O by impedance spectroscopy." Solid State Ionics 76, no. 3-4 (1995): 337–40. http://dx.doi.org/10.1016/0167-2738(94)00302-9.

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35

Yoshii, Yuya, Norihisa Hoshino, Takashi Takeda, and Tomoyuki Akutagawa. "Protonic Conductivity and Hydrogen Bonds in (Haloanilinium)(H2PO4) Crystals." Journal of Physical Chemistry C 119, no. 36 (2015): 20845–54. http://dx.doi.org/10.1021/acs.jpcc.5b06665.

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36

Konsta, Amalia A., Joseph Laudat, and Poly Pissis. "Dielectric investigation of the protonic conductivity in plant seeds." Solid State Ionics 97, no. 1-4 (1997): 97–104. http://dx.doi.org/10.1016/s0167-2738(97)00076-3.

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37

Ponomareva, Valentina G., and Galina V. Lavrova. "Influence of dispersed TiO2 on protonic conductivity of CsHSO4." Solid State Ionics 106, no. 1-2 (1998): 137–41. http://dx.doi.org/10.1016/s0167-2738(97)00482-7.

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38

Belonenko, M. B., and E. Yu Koleganova. "Low-temperature nonlinear lattices in ferroelectrics with protonic conductivity." Low Temperature Physics 26, no. 1 (2000): 47–50. http://dx.doi.org/10.1063/1.593861.

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39

Pathinettam Padiyan, D., S. John Ethilton, and K. Paulraj. "Protonic Conductivity and Photoconductivity Studies on H3PW12O40x21H2O Single Crystals." Crystal Research and Technology 35, no. 1 (2000): 87–94. http://dx.doi.org/10.1002/(sici)1521-4079(200001)35:1<87::aid-crat87>3.0.co;2-t.

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40

Careri, G., M. Geraci, A. Giansanti, and J. A. Rupley. "Protonic conductivity of hydrated lysozyme powders at megahertz frequencies." Proceedings of the National Academy of Sciences 82, no. 16 (1985): 5342–46. http://dx.doi.org/10.1073/pnas.82.16.5342.

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41

Wendler, Leonardo, Kethlinn Ramos та Dulcina Souza. "Influence of ZnO addition on microstructure and proton electrical conductivity of BaZr0.8Y0.2O3-δ ceramics". Processing and Application of Ceramics 15, № 2 (2021): 202–9. http://dx.doi.org/10.2298/pac2102202w.

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Sintering aids are widely used to promote densification and grain growth for electrolytes based on yttriumdoped barium zirconate. However, there are some discrepancies in the literature about the influence of these sintering aids on the microstructure development. Some authors consider that ZnO remains on grain boundaries, forming an amorphous phase that promotes sintering, and others proposed that ZnO forms a solid solution with barium zirconate. Even considering different mechanisms, it was proposed that ZnO addition compromised protonic conductivity. In this work BaZr0.8Y0.2O3-? (BZY20) was
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42

Ji, Ho-Il, Hyoungchul Kim, Hae-Weon Lee, et al. "Open-cell voltage and electrical conductivity of a protonic ceramic electrolyte under two chemical potential gradients." Physical Chemistry Chemical Physics 20, no. 22 (2018): 14997–5001. http://dx.doi.org/10.1039/c8cp01880d.

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Theoretical open-circuit voltage and electrical conductivity of BZY20 at 500 °C under O<sub>2</sub> and H<sub>2</sub>O chemical potential gradients in a range of interest for protonic ceramic fuel cells are investigated.
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43

Clark, D., J. Tong, A. Morrissey, A. Almansoori, I. Reimanis, and R. O'Hayre. "Anomalous low-temperature proton conductivity enhancement in a novel protonic nanocomposite." Phys. Chem. Chem. Phys. 16, no. 11 (2014): 5076–80. http://dx.doi.org/10.1039/c4cp00468j.

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A novel protonic ceramic composite is synthesized that comprises nanoscale nickel metal films at the grain boundaries of the proton-conducting ceramic, BaCe<sub>0.7</sub>Zr<sub>0.1</sub>Y<sub>0.1</sub>Yb<sub>0.1</sub>O<sub>3−δ</sub>. Low-temperature proton conductivity improvements of up to 46× are observed.
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44

Li, Chuanming, Yanwei Zeng, Zhentao Wang, Zhupeng Ye, Yuan Zhang, and Rui Shi. "Preparation of SDC–NC nanocomposite electrolytes with elevated densities: influence of prefiring and sintering treatments on their microstructures and electrical conductivities." RSC Advances 6, no. 102 (2016): 99615–24. http://dx.doi.org/10.1039/c6ra15680k.

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Elevated dense SDC–NC nanocomposites with a relative density of 91.6% can be obtained after prefiring at 500 °C and sintering at 800 °C and show the highest oxide ionic and protonic conductivity, ∼3.27 and 9.11 mS cm<sup>−1</sup> at 600 °C, respectively.
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45

Braun, Artur, Qianli Chen, and Arthur Yelon. "Hole and Protonic Polarons in Perovskites." CHIMIA International Journal for Chemistry 73, no. 11 (2019): 936–42. http://dx.doi.org/10.2533/chimia.2019.936.

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Electric charge transport is an essential process for all electrical and electrochemical energy systems, including inanimate and animate matter. In this issue on materials for energy conversion, we compare and discuss the role of electron holes and protons as charge carriers in solids. Specifically we outline how the temperature or thermal bath affect the charge carrier concentration and mobility for some metal oxides with the perovskite structure. The frequent observation that the conductivity becomes independent of the activation energy at the isokinetic temperature, known as the Meyer-Nelde
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46

Afif, Ahmed, Nikdalila Radenahmad, Juliana Zaini та ін. "Enhancement of proton conductivity through Yb and Zn doping in BaCe0.5Zr0.35Y0.15O3-δ electrolyte for IT-SOFCs". Processing and Application of Ceramics 12, № 2 (2018): 180–88. http://dx.doi.org/10.2298/pac1802180a.

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The new compositions of BaCe0.5Zr0.3Y0.15-xYbxZn0.05O3-? perovskite electrolytes (x = 0.1 and 0.15) were prepared by solid state synthesis and final sintering at 1500?C. The obtained ceramics were investigated using X-ray diffraction, scanning electron microscopy, thermo-gravimetric analysis and impedance spectroscopy. The refinement of XRD data confirmed cubic crystal structure with Pm3m space group for both samples. SEM morphology showed larger and compacted grains which enables obtaining of high density and high protonic conductivity. The relative densities of the samples were about 99% of
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47

Muda, N., Salmiah Ibrahim, Norlida Kamarulzaman, and Mohamed Nor Sabirin. "PVDF-HFP-NH4CF3SO3-SiO2 Nanocomposite Polymer Electrolytes for Protonic Electrochemical Cell." Key Engineering Materials 471-472 (February 2011): 373–78. http://dx.doi.org/10.4028/www.scientific.net/kem.471-472.373.

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This paper describes the preparation and characterization of proton conducting nanocomposite polymer electrolytes based a polyvinylidene fluoride-co-hexapropylene (PVDF-HFP) for protonic electrochemical cells. The electrolytes were characterized by Differential Scanning Calorimetry (DSC) and Impedance Spectroscopy (IS). It is observed that the crystallinity of the PVDF-HFP-NH4CF3SO3 system slightly increase upon addition of SiO2 nanofiller. The PVDF-HFP-NH4CF3SO3-SiO2 electrolytes reveals the existence of two conductivity maxima at 1 and 4 wt% of SiO2 concentration attributed to two percolatio
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48

Wan, Yanhong, Beibei He, Ranran Wang, Yihan Ling та Ling Zhao. "Effect of Co doping on sinterability and protonic conductivity of BaZr0.1Ce0.7Y0.1Yb0.1O3−δ for protonic ceramic fuel cells". Journal of Power Sources 347 (квітень 2017): 14–20. http://dx.doi.org/10.1016/j.jpowsour.2017.02.049.

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49

Pérez-Coll, Domingo, Juan Carlos Pérez-Flores, Narendar Nasani, Peter R. Slater, and Duncan P. Fagg. "Exploring the mixed transport properties of sulfur(vi)-doped Ba2In2O5 for intermediate-temperature electrochemical applications." Journal of Materials Chemistry A 4, no. 28 (2016): 11069–76. http://dx.doi.org/10.1039/c6ta02708c.

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The temperature dependence of the conductivity of Ba<sub>2</sub>In<sub>1.8</sub>S<sub>0.2</sub>O<sub>5+δ</sub> associated with different species, protonic, σ<sub>H</sub>, electronic, σ<sub>e</sub>, and oxide-ionic, σ<sub>o</sub>, under wet conditions.
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50

Garbaraczyk, J. E. "Protonic Conductivity and Thermal Stability of the Amorphous Hydrogen Periodate." Materials Science Forum 76 (January 1991): 87–90. http://dx.doi.org/10.4028/www.scientific.net/msf.76.87.

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