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Metal Phosphates and Pyrophosphates as Proton Conductors: Comparison
Please note this is a comparison between Version 2 by Montse Bazaga-García and Version 1 by Montse Bazaga-García.

     We review the progress in metal phosphate structural chemistry focused on proton conductivity properties and applications. Attention is paid to structure–property relationships, which ultimately determine the potential use of metal phosphates and derivatives in devices relying on proton conduction. The origin of their conducting properties, including both intrinsic and extrinsic conductivity, is rationalized in terms of distinctive structural features and the presence of specific proton carriers or the factors involved in the formation of extended hydrogen-bond networks. To make the exposition of this large class of proton conductor materials more comprehensive, we group/combine metal phosphates by their metal oxidation state, starting with metal (IV) phosphates and pyrophosphates, considering historical rationales and taking into account the accumulated body of knowledge of these compounds. We highlight the main characteristics of super protonic CsH2PO4, its applicability, as well as the affordance of its composite derivatives. We finish by discussing relevant structure–conducting property correlations for divalent and trivalent metal phosphates. Overall, emphasis is placed on materials exhibiting outstanding properties for applications as electrolyte components or single electrolytes in Polymer Electrolyte Membrane Fuel Cells and Intermediate Temperature Fuel Cells.

 

  • metal phosphate
  • proton conductivity
  • H-bond network
  • proton carriers
  • super protonic
  • metal pyrophosphate
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References

  1. Shivhare, A.; Kumara, A.; Srivastava, R. Metal phosphate catalysts to upgrade ligno-cellulose biomass into value-added chemicals and biofuels. Green Chem. 2021, 23, 3818–3841.
  2. Zhao, H.; Yuan, Z.-Y. Insights into Transition Metal Phosphate Materials for Efficient Electrocatalysis. ChemCatChem 2020, 12, 3797–3810.
  3. Chen, L.; Zhao, Y.; Yang, J.; Liu, D.; Wei, X.; Wang, X.; Zheng, Y. New Versatile Synthetic Route for the Preparation of Metal Phosphate Decorated Hydrogen Evolution Photocatalysts. Inorg. Chem. 2020, 59, 1566–1575.
  4. Goñi-Urtiaga, A.; Presvytes, D.; Scott, K. Solid acids as electrolyte materials for proton exchange membrane (PEM) electrol-ysis: Review. Int. J. Hydrog. Energy 2012, 37, 3358–3372.Goñi-Urtiaga, A.; Presvytes, D.; Scott, K. Solid acids as electrolyte materials for proton exchange membrane (PEM) electrolysis: Review. Int. J. Hydrog. Energy 2012, 37, 3358–3372.
  5. Paschos, O.; Kunze, J.; Stimming, U.; Maglia, F. A review on phosphate based, solid state, protonic conductors for interme-diate temperature fuel cells. J. Phys. Condens. Matter 2011, 23, 234110.Paschos, O.; Kunze, J.; Stimming, U.; Maglia, F. A review on phosphate based, solid state, protonic conductors for intermediate temperature fuel cells. J. Phys. Condens. Matter 2011, 23, 234110.
  6. Haile, S.M.; Chisholm, C.R.I.; Sasaki, K.; Boysen, D.A.; Uda, T. Solid acid proton conductors: From laboratory curiosities to fuel cell electrolytes. Faraday Discuss. 2007, 134, 17–39.
  7. Cheng, Q.; Zhao, X.; Yang, G.; Mao, L.; Liao, F.; Chen, F.; He, P.; Pan, D.; Chen, S. Recent advances of metal phosphates-based electrodes for high-performance metal ion batteries. Energy Storage Mater. 2021, 41, 842–882.
  8. Habraken, W.; Habibovic, P.; Epple, M.; Bohner, M. Calcium phosphates in biomedical applications: Materials for the fu-ture? Mater. Today 2015, 19, 69–87.Habraken, W.; Habibovic, P.; Epple, M.; Bohner, M. Calcium phosphates in biomedical applications: Materials for the future? Mater. Today 2015, 19, 69–87.
  9. Mohammad, N.; Mohamad, A.B.; Kadhum, A.A.H.; Loh, K.S. A review on synthesis and characterization of solid acid mate-rials for fuel cell applications. J. Power Sources 2016, 322, 77–92.Li, J.; Yi, M.; Zhang, L.; You, Z.; Liu, X.; Li, B. Energy related ion transports in coordination polymers. Nano Select. 2021, 1–19.
  10. Pica, M.; Donnadio, A.; Casciola, M. From microcrystalline to nanosized α-zirconium phosphate: Synthetic approaches and applications of an old material with a bright future. Coord. Chem. Rev. 2018, 374, 218–235.
  11. Wong, N.E.; Ramaswamy, P.; Lee, A.S.; Gelfand, B.S.; Bladek, K.J.; Taylor, J.M.; Spasyuk, D.M.; Shimizu, G.K.H. Tuning In-trinsic and Extrinsic Proton Conduction in Metal−Organic Frameworks by the Lanthanide Contraction. J. Am. Chem. Soc. 2017, 139, 14676–14683.Wong, N.E.; Ramaswamy, P.; Lee, A.S.; Gelfand, B.S.; Bladek, K.J.; Taylor, J.M.; Spasyuk, D.M.; Shimizu, G.K.H. Tuning Intrinsic and Extrinsic Proton Conduction in Metal−Organic Frameworks by the Lanthanide Contraction. J. Am. Chem. Soc. 2017, 139, 14676–14683.
  12. Horike, S.; Umeyama, D.; Inukai, M.; Itakura, T.; Kitagawa, S. Coordination-network-based ionic plastic crystal for anhy-drous proton conductivity. J. Am. Chem. Soc. 2012, 134, 7612–7615.Horike, S.; Umeyama, D.; Inukai, M.; Itakura, T.; Kitagawa, S. Coordination-network-based ionic plastic crystal for anhydrous proton conductivity. J. Am. Chem. Soc. 2012, 134, 7612–7615.
  13. Zhang, K.-M.; Lou, Y.-L.; He, F.-Y.; Duan, H.-B.; Huang, X.-Q.; Fan, Y.; Zhao, H.-R. The water-mediated proton conductivity of a 1D open framework inorganic-organic hybrid iron phosphate and its composite membranes. Inorg. Chem. Commun. 2021, 134, 109032.
  14. Yu, J.-W.; Yu, H.-J.; Ren, Q.; Zhang, J.; Zou, Y., Luo, H.-B.; Wang, L.; Ren, X.-M. Humidity-sensitive irreversible phase trans-formation of open-framework zinc phosphate and its water-assisted high proton conduction properties. Dalton Trans. 2021, 50, 8070–8075.Yu, J.-W.; Yu, H.-J.; Ren, Q.; Zhang, J.; Zou, Y., Luo, H.-B.; Wang, L.; Ren, X.-M. Humidity-sensitive irreversible phase transformation of open-framework zinc phosphate and its water-assisted high proton conduction properties. Dalton Trans. 2021, 50, 8070–8075.
  15. Su, X.; Yao, Z.; Ye, Y.; Zeng, H.; Xu, G.; Wu, L.; Ma, X.; Chen, Q.-H.; Wang, L.; Zhang, Z.; et al. 40-Fold Enhanced Intrinsic Proton Conductivity in Coordination Polymers with the Same Proton-Conducting Pathway by Tuning Metal Cation Nodes. Inorg. Chem. 2016, 55, 983–986.
  16. Shi, J.; Wang, K.; Li, J.; Zeng, H.; Zhang, Q.; Lin, Z. Exploration of new water stable proton-conducting materials in an ami-no acid-templated metal phosphate system. Dalton Trans. 2018, 47, 654–658.Shi, J.; Wang, K.; Li, J.; Zeng, H.; Zhang, Q.; Lin, Z. Exploration of new water stable proton-conducting materials in an amino acid-templated metal phosphate system. Dalton Trans. 2018, 47, 654–658.
  17. Zhang, K.-M.; He, F.-Y.; Duan, H.-B.; Zhao, H.-R. An alkali metal ion-exchanged metal-phosphate (C2H10N2)xNa1−x[Mn2(PO4)2] with high proton conductivity of 10−2 S·cm−1. Inorg. Chem. 2019, 58, 6639–6646.
  18. Zhang, K.-M.; Jia, Y.; Gu, Y., He, F.-Y.; Zhao, H.-R. A facile and efficient method to improve the proton conductivity of open framework metal phosphates under aqueous condition. Inorg. Chem. Commun. 2020, 120, 108128.
  19. Umeyama, D.; Horike, S.; Inukai, M.; Kitagawa, S. Integration of Intrinsic Proton Conduction and Guest-Accessible Nano-space into a Coordination Polymer. J. Am. Chem. Soc. 2013, 135, 11345–11350.Umeyama, D.; Horike, S.; Inukai, M.; Kitagawa, S. Integration of Intrinsic Proton Conduction and Guest-Accessible Nanospace into a Coordination Polymer. J. Am. Chem. Soc. 2013, 135, 11345–11350.
  20. Baranov, A.I.; Khiznichenko, V.P.; Sandler, V.A.; Shuvalov, L.A. Frequency dielectric dispersion in the ferroelectric and superionic phases of CsH2PO4. Ferroelectrics 1988, 81, 183–186.
  21. Colomban, P. Chemistry of Solid-State Materials. In Proton Conductors: Solid, Membranes and Gels-Materials and Devices; Cam-bridge University Press: Cambridge, UK, 1992.Colomban, P. Chemistry of Solid-State Materials. In Proton Conductors: Solid, Membranes and Gels-Materials and Devices; Cambridge University Press: Cambridge, UK, 1992.
  22. Fragua, D.M.; Castillo, J.; Castillo, R.; Vargas, R.A. New amorphous phase KnH2PnO3n+1(n>>1) in KH2PO4. Rev. Latin Am. Metal. Mat. 2009, 2, 491–497.
  23. Skou, E.; Andersen, I.G.K.; Simonsen, K.E.; Andersen, E.K. Is UO2HPO4·4H2O a proton conductor? Solid State Ion. 1983, 9, 1041–1047.Botez, C.E.; Tackett, R.J.; Hermosillo, J.D.; Zhang, J.; Zhao, Y.; Wang, L. High pressure synchrotron x-ray diffraction studies of superprotonic transitions in phosphate solid acids. Solid State Ion. 2012, 213, 58–62.
  24. Cabeza, A.; Martinez, M.; Benavente, J.; Bruque, S. Current rectification by H3OUO2PO4 3H2O (HUP) thin films in electrolyte media. Solid State Ion. 1992, 51, 127–131.Baranov, A.I. Crystals with disordered hydrogen-bond networks and superprotonic conductivity. Review. Crystallogr. Rep. 2003, 48, 1012–1037.
  25. Barboux, P.; Morineau, R.; Livage, J. Protonic conductivity in hydrates. Solid State Ion. 1988, 27, 221–225.Bagryantseva, I.N.; Gaydamaka, A.A.; Ponomareva, V.G. Intermediate temperature proton electrolytes based on cesium dihydrogen phosphate and Butyral polymer. Ionics 2020, 26, 1813–1818.
  26. Barboux, P.; Livage, J. Ionic conductivity in fibrous Ce(HPO4)2·(3+x)H2O. Solid State Ion. 1989, 34, 47–52.Dreßler, C.; Sebastiani, D. Effect of anion reorientation on proton mobility in the solid acids family CsHyXO4 (X = S, P, Se, y = 1, 2) from ab initio molecular dynamics simulations. Phys. Chem. Chem. Phys. 2020, 22, 10738–10752.
  27. Li, J.; Yi, M.; Zhang, L.; You, Z.; Liu, X.; Li, B. Energy related ion transports in coordination polymers. Nano Select. 2021, 1–19.Taninouchi, Y.K.; Uda, T.; Awakura, Y.; Ikeda, A.; Haile, S.M. Dehydration behavior of the superprotonic conductor CsH2PO4 at moderate temperatures: 230 to 260 °C. J. Mater. Chem. 2007, 17, 3182–3189.
  28. Steele, B.C.H.; Heinzel, A. Materials for fuel-cell technologies. Nature 2001, 414, 345–352.Mathur, L.; Kim, I.-H.; Bhardwaj, A.; Singh, B.; Park, J.-Y.; Song, S.-J. Structural and electrical properties of novel phosphate based composite electrolyte for low-temperature fuel cells. Composites Part B 2020, 202, 108405.
  29. Wei, J. Proton-Conducting Materials Used as Polymer Electrolyte Membranes in Fuel Cells (ch 9). In Polymer-Based Multi-functional Nanocomposites and Their Applications; Song, K., Liu, C., Guo, J.Z., Eds.; Elsevier: Amsterdam, The Netherlands, 2019; Chapter 9, pp. 245–260.Otomo, J.; Tamaki, T.; Nishida, S.; Wang, S.; Ogura, M.; Kobayashi, T.; Wen, C.-J.; Nagamoto, H.; Takahashi, H. Effect of water vapor on proton conduction of cesium dihydrogen phosphate and application to intermediate temperature fuel cells. J. Appl. Electrochem. 2005, 35, 865–870.
  30. Sazali, N.; Salleh, W.N.W.; Jamaludin, A.S.; Razali, M.N.M. New Perspectives on Fuel Cell Technology: A Brief Review. Membranes 2020, 10, 99.Uda, T.; Haile, S.M. Thin-membrane solid-acid fuel cell. Electrochem. Solid State Lett. 2005, 8, A245–A246.
  31. Dupuis, A.-C. Proton exchange membranes for fuel cells operated at medium temperatures: Materials and experimental techniques. Prog. Mater. Sci. 2011, 56, 289–327.Navarrete, L.; Andrio, A.; Escolástico, S.; Moya, S.; Compañ, V.; Serra, J.M. Protonic Conduction of Partially-Substituted CsH2PO4 and the Applicability in Electrochemical Devices. Membranes 2019, 9, 49.
  32. Peighambardoust, S.J.; Rowshanzamir, S.; Amjadi, M. Review of the proton exchange membranes for fuel cell applications. Int. J. Hydrog. Energy 2010, 35, 9349–9384.Ponomareva, V.G.; Bagryantseva, I.N.; Gaydamaka, A.A. Study of the Phase Composition and Electrotransport Properties of the Systems Based on Mono- and Disubstituted Phosphates of Cesium and Rubidium. Chem. Sustain. Dev. 2019, 27, 238–245.
  33. Mauritz, K.A.; Moore, R.B. State of understanding of Nafion. Chem. Rev. 2004, 104, 4535–4585.Martsinkevich, V.V.; Ponomareva, V.G. Double salts Cs1-xMxH2PO4 (M = Na, K, Rb) as proton conductors. Solid State Ion. 2012, 225, 236–240.
  34. Hickner, M.A.; Ghassemi, H.; Kim, Y.S.; Einsla, B.R.; McGrath, J.E. Alternative polymer systems for proton exchange mem-branes (PEMs). Chem. Rev. 2004, 104, 4587–4612.Ponomareva, V.G.; Bagryantseva, I.N. Superprotonic CsH2PO4-CsHSO4 solid solutions. Inorg. Mater. 2012, 48, 187–194.
  35. Han, X.; Xie, Y.; Liu, D.; Chen, Z.; Zhang, H.; Pang, J.; Jiang, Z. Synthesis and properties of novel poly(arylene ether)s with densely sulfonated units based on carbazole derivative. J. Membr. Sci. 2019, 589, 117230.Ponomareva, V.G.; Uvarov, N.F.; Lavrova, G.V.; Hairetdinov, E.F. Composite protonic solid electrolytes in the CsHSO4-SiO2 system. Solid State Ion. 1996, 90, 161–166.
  36. Kuzmenko, M.; Poryadchenko, N. Perspective materials for application in fuel-cell technologies. In Fuel Cell Technologies: State and Perspectives; Sammes. N., Ed.; Springer: Dordrecht, The Netherlands, 2005; pp. 253–258.Ponomareva, V.G.; Shutova, E.S.; Matvienko, A.A. Conductivity of Proton Electrolytes Based on Cesium Hydrogen Sulfate Phosphate. Inorg. Mater. 2004, 40, 721–728.
  37. Lee, K.-S.; Maurya, S.; Kim, Y.S.; Kreller, C.R.; Wilson, M.S.; Larsen, D.; Elangovan, S.E.; Mukundan, R. Intermediate temper-ature fuel cells via an ion-pair coordinated polymer electrolyte. Energy Env. Sci. 2018, 11, 979–987.Otomo, J.; Minagawa, N.; Wen, C.-J.; Eguchi, K.; Takahashi, H. Protonic conduction of CsH2PO4 and its composite with silica in dry and humid atmospheres. Solid State Ion. 2003, 156, 357–369.
  38. Norby, T. Solid-state protonic conductors: Principles, properties, progress and prospects. Solid State Ion. 1999, 125, 1–11.Ponomareva, V.G.; Shutova, E.S. High-temperature behavior of CsH2PO4 and CsH2PO4-SiO2 composites. Solid State Ion. 2007, 178, 729–734.
  39. Li, Q.; He, R.; Jensen, J.O.; Bjerrum, N.J. Approaches and Recent Development of Polymer Electrolyte Membranes for Fuel Cells Operating above 100 °C. Chem. Mater. 2003, 15, 4896–4915.Singh, D.; Singh, J.; Kumar, P.; Veer, D.; Kumar, D.; Katiyar, R.S.; Kumar, A.; Kumar, A. The Influence of TiO2 on the Proton Conduction and Thermal Stability of CsH2PO4 Composite Electrolytes. S. Afr. J. Chem. Eng. 2021, 37, 227–236.
  40. Loreti, G.; Facci, A.L.; Ubertini, S. High-Efficiency Combined Heat and Power through a High-Temperature Polymer Elec-trolyte Membrane Fuel Cell and Gas Turbine Hybrid System. Sustainability 2021, 13, 12515.Singh, D.; Kumar, P.; Singh, J.; Veer, D.; Kumar, A.; Katiyar, R.S. Structural, thermal and electrical properties of composites electrolytes (1−x) CsH2PO4/x ZrO2 (0 ≤ x ≤ 0.4) for fuel cell with advanced electrode. SN Appl. Sci. 2021, 3, 46.
  41. Boysen, D.A.; Uda, T.; Chisholm, C.R.I.; Haile, S.M. High-Performance Solid Acid Fuel Cells Through Humidity Stabiliza-tion. Science 2004, 303, 68–70.Veer, D.; Kumar, P.; Singh, D.; Kumar, D.; Katiyar, R.S. A synergistic approach to achieving high conduction and stability of CsH2PO4/NaH2PO4/ZrO2 composites for fuel cells. Mater. Adv. 2021, 3, 409–417.
  42. Zhang, J.; Aili, D.; Lu, S.; Li, Q.; Jiang, S.P. Advancement toward Polymer Electrolyte Membrane Fuel Cells at Elevated Temperatures. AAAS Res. 2020, 2020, 9089405.Aili, D.; Gao, Y.; Han, J.; Li, Q. Acid-base chemistry and proton conductivity of CsHSO4, CsH2PO4 and their mixtures with N-heterocycles. Solid State Ion. 2017, 306, 13–19.
  43. Clearfield, A.; Smith, S.D. The crystal structure of zirconium phosphate and the mechanism of its ion exchange behavior. J. Colloid Interface Sci. 1968, 28, 325–330.Bagryantseva, I.N.; Ponomareva, V.G.; Khusnutdinov, V.R. Intermediate temperature proton electrolytes based on cesium dihydrogen phosphate and poly(vinylidene fluoride-co-hexafluoropropylene). J. Mater. Sci. 2021, 56, 14196–14206.
  44. Clearfield, A.; Smith, G.D. Crystallography and structure of alpha-zirconium bis(monohydrogen orthophosphate) mono-hydrate. Inorg. Chem. 1969, 8, 431–436.Ponomareva, V.G.; Bagryantseva, I.N.; Shutova, E.S. Hybrid systems based on nanodiamond and cesium dihydrogen phosphate. Mater. Today 2020, 25, 521–524.
  45. Troup, J.M.; Clearfield, A. Mechanism of ion exchange in zirconium phosphates. 20. Refinement of the crystal structure of .alpha.-zirconium phosphate. Inorg. Chem. 1977, 16, 3311–3314.Ma, N.; Kosasang, S.; Yoshida, A.; Horike, S. Proton-conductive coordination polymer glass for solid-state anhydrous proton batteries. Chem. Sci. 2021, 12, 5818–5824.
  46. Casciola, M. From layered zirconium phosphates and phosphonates to nanofillers for ionomeric membranes. Solid State Ion. 2019, 336, 1–10.Zhao, H.-R.; Xue, C.; Li, C.-P.; Zhang, K.-M.; Luo, H.-B.; Liu, S.-X.; Ren, X.-M. A Two-Dimensional inorganic−organic hybrid solid of manganese(II) hydrogenophosphate showing high proton conductivity at room temperature. Inorg. Chem. 2016, 55, 8971–8975.
  47. Ogawa, T.; Ushiyam, H.; Lee, J.-M.; Yamaguchi, T.; Yamashita, K. Theoretical Studies on Proton Transfer among a High Density of Acid Groups: Surface of Zirconium Phosphate with Adsorbed Water Molecules. J. Phys. Chem. C 2011, 115, 5599–5606.Wang, M.; Luo, H.-B.; Liu, S.-X.; Zou, Y.; Tian, Z.-F.; Li, L.; Liu, J.-L.; Ren, X.-M. Water assisted high proton conductance in a highly thermally stable and superior water-stable open-framework cobalt phosphate. Dalton Trans. 2016, 45, 19466–19472.
  48. Alberti, G.; Casciola, M.; Costantino, U. Inorganic ion-exchange pellicles obtained by delamination of α-zirconium phos-phate crystals. J. Colloid Interface Sci. 1985, 107, 256–263.Umeyama, D.; Horike, S.; Inukai, M.; Itakura, T.; Kitagawa, S. Inherent Proton Conduction in a 2D Coordination Framework. J. Am. Chem. Soc. 2012, 134, 12780–12785.
  49. Alberti, G.; Casciola, M.; Costantino, U.; Leonardi, M. AC conductivity of anhydrous pellicular zirconium phosphate in hydrogen form. Solid State Ion. 1984, 14, 289–295.Inukai, M.; Horike, S.; Chen, W.; Umeyama, D.; Itakurad, T.; Kitagawa, S. Template-directed proton conduction pathways in a coordination framework. J. Mater. Chem. A. 2014, 2, 10404–10409.
  50. Casciola, M.; Costantino, U.; D’Amico, S. Protonic conduction of intercolation compounds of α-zirconium phosphate with propylamine. Solid State Ion. 1986, 22, 127–133.Zhao, H.R.; Jia, Y.; Gu, V.; He, F.Y.; Zhang, K.M.; Tian, Z.F.; Liu, J.L. A 3D open-framework iron hydrogenophosphate showing high proton conductance under water and aqua-ammonia vapor. RSC Adv. 2020, 10, 9046–9051.
  51. Alberti, G.; Casciola, M.; Cavalaglio, S.; Vivani, R. Proton conductivity of mesoporous zirconium phosphate pyrophos-phate. Solid State Ion. 1999, 125, 91–97.Zima, V.; Lii, K.-H. Synthesis and characterization of a novel one-dimensional iron phosphate: [C4H12N2]1.5[Fe2(OH)(H2PO4)(HPO4)2(PO4)]·0.5H2O. J. Chem. Soc. Dalton Trans. 1998, 24, 4109–4112.
  52. Alberti, G.; Casciola, M.; Donnadio, A.; Piaggio, P.; Pica, M.; Sisani, M. Preparation and characterisation of α-layered zirco-nium phosphate sulfophenylenphosphonates with variable concentration of sulfonic groups. Solid State Ion. 2005, 176, 2893–2898.Lii, K.-H.; Huang, Y.-F. Large tunnels in the hydrothermally synthesized open-framework iron phosphate (NH3(CH2)3NH3)2[Fe4(OH)3(HPO4)2(PO4)3]·xH2O. Chem. Commun. 1997, 9, 839–840.
  53. Gui, D.; Zheng, T.; Xie, J.; Cai, Y.; Wang, Y.; Chen, L.; Diwu, J.; Chai, Z.; Wang, S. Significantly dense two-dimensional hy-drogen-bond network in a layered zirconium phosphate leading to high proton conductivities in both water-assisted low-temperature and anhydrous intermediate-temperature regions. Inorg. Chem. 2016, 55, 12508–12511.Bazaga-García, M.; Colodrero, R.M.P.; Papadaki, M.; Garczarek, P.; Zon, J.; Olivera-Pastor, P.; Losilla, E.R.; Reina, L.L.; Aranda, M.A.; Choquesillo-Lazarte, D.; et al. Guest Molecule-Responsive Functional Calcium Phosphonate Frameworks for Tuned Proton Conductivity. J. Am. Chem. Soc. 2014, 136, 5731–5739.
  54. Yu, J.-W.; Yu, H.-J.; Yao, Z.-Y.; Li, Z.-H.; Ren, Q.; Luo, H.-B.; Zou, Y.; Wang, L.; Ren, X.-M. A water-stable open-framework zirconium(IV) phosphate and its water-assisted high proton conductivity. CrystEngComm 2021, 23, 6093–6097.Lim, D.-W.; Kitagawa, H. Proton Transport in Metal−Organic Frameworks. Chem. Rev. 2020, 120, 8416–8467.
  55. Gui, D.; Dai, X.; Tao, Z.; Zheng, T.; Wang, X.; Silver, M.A.; Shu, J.; Chen, L.; Wang, Y.; Zhang, T.; et al. Unique proton trans-portation pathway in a robust inorganic coordination polymer leading to intrinsically high and sustainable anhydrous proton conductivity. J. Am. Chem. Soc. 2018, 140, 6146–6155.Mamlouk, M.; Scott, K. A boron phosphate-phosphoric acid composite membrane for medium temperature proton exchange membrane fuel cells. J. Power Sources 2015, 286, 290–298.
  56. Kusoglu, A.; Weber, A.Z. New Insights into Perfluorinated Sulfonic-Acid Ionomers. Chem. Rev. 2017, 117, 987–1104.Pusztai, P.; Haspel, H.; Tóth, I.Y.; Tombácz, E.; László, K.; Kukovecz, Á.; Kónya, Z. Structure-Independent Proton Transport in Cerium(III) Phosphate Nanowires. ACS Appl. Mater. Interfaces 2015, 7, 9947–9956.
  57. Alberti, G.; Casciola, M.; Capitani, D.; Donnadio, A.; Narducci, R.; Pica, M.; Sganappa, M. Novel Nafion–zirconium phos-phate nanocomposite membranes with enhanced stability of proton conductivity at medium temperature and high relative humidity. Electrochim. Acta 2007, 52, 8125–8132.Mu, Y.; Wang, Y.Y.; Li, Y.; Li, J.Y.; Yu, J.H. Organotemplate-free synthesis of an open-framework magnesium aluminophosphate with proton conduction properties. Chem. Commun. 2015, 51, 2149–2151.
  58. Grot, W.G.; Rajendran, G.; Hendrickson, J.S. International Patent Application No. PCT/US96/03804, International Publication No. WO 96/2975, 26, September, 1996.Petersen, H.; Stefmann, N.; Fischer, M.; Zibrowius, I.R.; Philippi, W.; Schmidt, W.; Weidenthaler, C. Crystal structures of two titanium phosphate-based proton conductors: Ab initio structure solution and materials properties. Inorg. Chem. 2022, 61, 2379–2390.
  59. Alberti, G.; Casciola, M.; Pica, M.; Tarpanelli, T.; Sganappa, M. New Preparation Methods for Composite Membranes for Medium Temperature Fuel Cells Based on Precursor Solutions of Insoluble Inorganic Compounds. Fuel Cells 2005, 5, 366–374.Clearfield, A.; Smith, S.D. The crystal structure of zirconium phosphate and the mechanism of its ion exchange behavior. J. Colloid Interface Sci. 1968, 28, 325–330.
  60. Casciola, M.; Bagnasco, G.; Donnadio, A.; Micoli, L.; Pica, M.; Sganappa, M.; Turco, M. Conductivity and Methanol Permea-bility of Nafion–Zirconium Phosphate Composite Membranes Containing High Aspect Ratio Filler Particles. Fuel Cells 2009, 9, 394–400.Clearfield, A.; Smith, G.D. Crystallography and structure of alpha-zirconium bis(monohydrogen orthophosphate) monohydrate. Inorg. Chem. 1969, 8, 431–436.
  61. Arbizzani, C.; Donnadio, A.; Pica, M.; Sganappa, M.; Varzi, A.; Casciola, M.; Mastragostino, M. Methanol permeability and performance of Nafion–zirconium phosphate composite membranes in active and passive direct methanol fuel cells. J. Power Sources 2010, 195, 7751–7756.Troup, J.M.; Clearfield, A. Mechanism of ion exchange in zirconium phosphates. 20. Refinement of the crystal structure of .alpha.-zirconium phosphate. Inorg. Chem. 1977, 16, 3311–3314.
  62. Pica, M.; Donnadio, A.; Casciola, M.; Cojocaru, P.; Merlo, L. Short side chain perfluorosulfonic acid membranes and their composites with nanosized zirconium phosphate: Hydration, mechanical properties and proton conductivity. J. Mater. Chem. 2012, 22, 24902–24908.Casciola, M. From layered zirconium phosphates and phosphonates to nanofillers for ionomeric membranes. Solid State Ion. 2019, 336, 1–10.
  63. Pica, M.; Donnadio, A.; Capitani, D.; Vivani, R.; Troni, E.; Casciola, M. Advances in the Chemistry of Nanosized Zirconium Phosphates: A New Mild and Quick Route to the Synthesis of Nanocrystals. Inorg. Chem. 2011, 50, 11623–11630.Gui, D.; Zheng, T.; Xie, J.; Cai, Y.; Wang, Y.; Chen, L.; Diwu, J.; Chai, Z.; Wang, S. Significantly dense two-dimensional hydrogen-bond network in a layered zirconium phosphate leading to high proton conductivities in both water-assisted low-temperature and anhydrous intermediate-temperature regions. Inorg. Chem. 2016, 55, 12508–12511.
  64. Bauer, F.; Willert-Porada, M. Comparison between Nafion and a Nafion zirconium phosphate nanocomposite in fuel cell applications. Fuel Cells 2006, 6, 261–269.Yu, J.-W.; Yu, H.-J.; Yao, Z.-Y.; Li, Z.-H.; Ren, Q.; Luo, H.-B.; Zou, Y.; Wang, L.; Ren, X.-M. A water-stable open-framework zirconium(IV) phosphate and its water-assisted high proton conductivity. CrystEngComm 2021, 23, 6093–6097.
  65. Casciola, M.; Cojocaru, P.; Donnadio, A., Giancola, S.; Merlo, L.; Nedellec, Y.; Pica, M.; Subianto, S. Zirconium phosphate reinforced short side chain perflurosulfonic acid membranes for medium temperature proton exchange membrane fuel cell application. J. Power Sources 2014, 262, 407–413.Gui, D.; Dai, X.; Tao, Z.; Zheng, T.; Wang, X.; Silver, M.A.; Shu, J.; Chen, L.; Wang, Y.; Zhang, T.; et al. Unique proton transportation pathway in a robust inorganic coordination polymer leading to intrinsically high and sustainable anhydrous proton conductivity. J. Am. Chem. Soc. 2018, 140, 6146–6155.
  66. Yang, C.; Srinivasan, S.; Aricò, A.S.; Creti, P.; Baglio, V.; Antonucci, V. Composition Nafion/zirconium phosphate mem-branes for direct methanol fuel cell operation at high temperature. Electrochem. Solid-State Lett. 2001, 4, A31–A34.Alberti, G.; Cardini-Galli, P.; Costantino, U.; Torracca, E. Crystalline insoluble salts of polybasic metals—I Ion-exchange properties of crystalline titanium phosphate. J. Inorg. Nucl. Chem. 1967, 29, 571–578.
  67. Yang, C.; Costamagna, P.; Srinivasan, S.; Benziger, J.; Bocarsly, A.B. Approaches and technical challenges to high tempera-ture operation of proton exchange membrane fuel cells. J. Power Sources 2001, 103, 1–9.Christensen, A.N.; Anderson, E.K.; Andersen, I.G.; Alberti, G.; Nielsen, M.; Lehmann, E.K. X-Ray Powder diffraction study of layer compounds. The crystal structure of α-Ti (HPO4)2·H2O and a proposed structure for γ-Ti (H2PO4)(PO4)·2H2O. Acta Chem. Scand. 1990, 44, 865–872.
  68. Costamagna, P.; Yang, C.; Bocarsly, A.B.; Srinivasan, S. Nafion (R) 115/zirconium phosphate composite membranes for op-eration of PEMFCs above 100 °C. Electrochim. Acta 2002, 47, 1023–1033.Li, Y.J.; Whittingham, M.S. Hydrothermal synthesis of new metastable phases: Preparation and intercalation of a new layered titanium phosphate. Solid State Ion. 1993, 63, 391–395.
  69. Yang, C.; Srinivasan, S.; Bocarsly, A.B.; Tulyani, S.; Benziger, J.B. A comparison of physical properties and fuel cell perfor-mance of Nafion and zirconium phosphate/Nafion composite membranes. J. Membr. Sci. 2004, 237, 145–161.Kőrösi, L.; Papp, S.; Dékány, I. A layered titanium phosphate Ti2O3(H2PO4)2·2H2O with rectangular morphology: Synthesis, structure, and cysteamine intercalation. Chem. Mater. 2010, 22, 4356–4363.
  70. Lee, H.-K.; Kim, J.-I.; Park, J.-H.; Lee, T.-H. A study on self-humidifying PEMFC using Pt-ZrP-Nafion composite membrane. Electrochim. Acta 2004, 50, 761–768.Ekambaram, S.; Serre, C.; Férey, G.; Sevov, S.C. Hydrothermal synthesis and characterization of an ethylenediamine-templatedmixed-valence titanium phosphate. Chem. Mater. 2000, 12, 444–449.
  71. Escorihuela, J.; Narducci, R.; Compañ, V.; Costantino, F. Proton Conductivity of Composite Polyelectrolyte Membranes with Metal-Organic Frameworks for Fuel Cell Applications. Adv. Mater. Interfaces 2019, 6, 1801146.Krogh Andersen, A.M.; Norby, P.; Hanson, J.C.; Vogt, T. Preparation and characterization of a new 3-dimensional zirconium hydrogen phosphate, τ-Zr(HPO4)2. Determination of the complete crystal structure combining synchrotron X-ray single-crystal diffraction and neutron powder diffraction. Inorg. Chem. 1998, 37, 876–881.
  72. Liu, K.L.; Lee, H.C.; Wang, B.Y.; Lue, S.J.; Lu, C.Y.; Tsai, L.D.; Fang, J.; Chao, C.Y. Sulfonated poly(styrene-block-(ethylene-ran-butylene)-block-styrene (SSEBS)-zirconium phosphate) (ZrP) composite membranes for direct methanol fuel cells. J. Membr. Sci. 2015, 495, 110–120.Bortun, A.I.; Khainakov, S.A.; Bortun, L.N.; Poojary, D.M.; Rodriguez, J.; Jose, R. Garcia, J.R.; Clearfield, A. Synthesis and characterization of two novel fibrous titanium phosphates Ti2O(PO4)2·2H2O. Chem. Mater. 1997, 9, 1805–1811.
  73. Hu, H.; Ding, F.; Ding, H.; Liu, J.; Xiao, M.; Meng, Y.; Sun, L. Sulfonated poly(fluorenyl ether ketone)/Sulfonated α-zirconium phosphate Nanocomposite membranes for proton exchange membrane fuel cells. Adv. Compos. Hybrid Mater. 2020, 3, 498–507.Salvadó, M.A.; Pertierra, P.; García-Granda, S.; García, J.R.; Fernández-Diaz, M.T.; Dooryhee, E. Crystal structure, including H-atom positions, of Ti2O(PO4)2·(H2O)2 determined from synchrotron X-ray and neutron powder data. Eur. J. Solid State Inorg. Chem. 1997, 34, 1237–1247.
  74. Pandey, J.; Seepana, M.M.; Shukla, A. Zirconium phosphate based proton conducting membrane for DMFC application. Int. J. Hydrog. 2015, 40, 9410–9421.Babaryk, A.A.; Adawy, A.; García, I. Trobajo, C.; Amghouz, Z.; Colodrero, R.M.P. Cabeza, A.; Olivera-Pastor, P.; Bazaga-García, M.; dos Santos-Gómez, L. Structural and proton conductivity studies of fibrous π-Ti2O(PO4)2·2H2O: Application in chitosan-based composite membranes. Dalton Trans. 2021, 50, 7667–7677.
  75. He, R.; Li, Q.; Xiao, G.; Bjerrum, N.J. Proton conductivity of phosphoric acid doped polybenzimidazole and its composites with inorganic proton conductors. J. Membr. Sci. 2003, 226, 169–184.Bruque, S.; Aranda, M.A.G.; R. Losilla, E.; Olivera-Pastor, P.; Maireles-Torres, P. Synthesis optimization and crystal structures of layered metal(IV) hydrogen phosphates, .alpha.-M(HPO4)2.cntdot.H2O (M = Ti, Sn, Pb). Inorg. Chem. 1995, 34, 893–899.
  76. Gouda, M.H.; Tamer, T.M.; Konsowa, A.H.; Farag, H.A.; Mohy Eldin, M.S. Organic-Inorganic Novel Green Cation Exchange Membranes for Direct Methanol Fuel Cells. Energies 2021, 14, 4686.Huang, W.; Komarneni, S.; Noh,Y.D.; Ma, J.; Chen, K.; Xue, D.; Xuea, X.; Jiang, B. Novel inorganic tin phosphate gel: Multifunctional material. Chem. Commun. 2018, 54, 2682–2685.
  77. Alberti, G.; Cardini-Galli, P.; Costantino, U.; Torracca, E. Crystalline insoluble salts of polybasic metals—I Ion-exchange properties of crystalline titanium phosphate. J. Inorg. Nucl. Chem. 1967, 29, 571–578.Zhang, J.; Aili, D.; Lu, S.; Li, Q.; Jiang, S.P. Advancement toward Polymer Electrolyte Membrane Fuel Cells at Elevated Temperatures. AAAS Res. 2020, 2020, 9089405.
  78. Christensen, A.N.; Anderson, E.K.; Andersen, I.G.; Alberti, G.; Nielsen, M.; Lehmann, E.K. X-Ray Powder diffraction study of layer compounds. The crystal structure of α-Ti (HPO4)2·H2O and a proposed structure for γ-Ti (H2PO4)(PO4)·2H2O. Acta Chem. Scand. 1990, 44, 865–872.Ansari, Y.; Telpriore, G.; Tucker, C.; Angell, A. A novel, easily synthesized, anhydrous derivative of phosphoric acid for use in electrolyte with phosphoric acid-based fuel cells. J. Power Sources 2013, 237, 47–51.
  79. Li, Y.J.; Whittingham, M.S. Hydrothermal synthesis of new metastable phases: Preparation and intercalation of a new lay-ered titanium phosphate. Solid State Ion. 1993, 63, 391–395.Sato, Y.; Shen, Y.; Nishida, M.; Kanematsu, W.; Hibino, T. Proton Conduction in Non-Doped and Acceptor-Doped Metal Pyrophosphate (MP2O7) Composite Ceramics at Intermediate Temperatures. J. Mater. Chem. 2012, 22, 3973–3981.
  80. Kőrösi, L.; Papp, S.; Dékány, I. A layered titanium phosphate Ti2O3(H2PO4)2·2H2O with rectangular morphology: Synthesis, structure, and cysteamine intercalation. Chem. Mater. 2010, 22, 4356–4363.Singh, B.; Kima, J.-H.; Park, J.-Y.; Song, S.-J. Dense composite electrolytes of Gd3+-doped cerium phosphates for low-temperature proton-conducting ceramic-electrolyte fuel cells. Ceram. Inter. 2015, 41, 4814–4821.
  81. Ekambaram, S.; Serre, C.; Férey, G.; Sevov, S.C. Hydrothermal synthesis and characterization of an ethylenedia-mine-templatedmixed-valence titanium phosphate. Chem. Mater. 2000, 12, 444–449.Nagao, M.; Kamiya, T.; Heo, P.; Tomita, A.; Hibino, T.; Sano, M. Proton conduction in In3+-doped SnP2O7 at intermediate temperatures. J. Electrochem. Soc. 2006, 153, 1604–1609.
  82. Krogh Andersen, A.M.; Norby, P.; Hanson, J.C.; Vogt, T. Preparation and characterization of a new 3-dimensional zirconi-um hydrogen phosphate, τ-Zr(HPO4)2. Determination of the complete crystal structure combining synchrotron X-ray sin-gle-crystal diffraction and neutron powder diffraction. Inorg. Chem. 1998, 37, 876–881.Nagao, M.; Takeuchi, A.; Heo, P.; Hibino, T.; Sano, M.; Tomita, A. A proton-conducting In3 + -doped SnP2O7 electrolyte for intermediate-temperature fuel cells. Electrochem. Solid-State Lett. 2006, 9, A105.
  83. Mileo, P.G.M.; Kundu, T.; Semino, R.; Benoit, V.; Steunou, N.; Llewellyn, P.L.; Serre, C.; Maurin, G.; Devautour-Vinot, S. Highly Efficient Proton Conduction in a Three-Dimensional Titanium Hydrogen Phosphate. Chem. Mater. 2017, 29, 7263–7271.Jin, Y.; Fujiwara, K.; Hibino, T. High temperature, low humidity proton exchange membrane based on an inorganic–organic hybrid structure. Electrochem. Solid-State Lett. 2010, 13, B8.
  84. Bortun, A.I.; Khainakov, S.A.; Bortun, L.N.; Poojary, D.M.; Rodriguez, J.; Jose, R. Garcia, J.R.; Clearfield, A. Synthesis and characterization of two novel fibrous titanium phosphates Ti2O(PO4)2·2H2O. Chem. Mater. 1997, 9, 1805–1811.Jin, Y.; Shen, Y.; Hibino, T. Proton conduction in metal pyrophosphates (MP2O7) at intermediate temperatures. J. Mater. Chem. 2010, 20, 6214–6217.
  85. Salvadó, M.A.; Pertierra, P.; García-Granda, S.; García, J.R.; Fernández-Diaz, M.T.; Dooryhee, E. Crystal structure, including H-atom positions, of Ti2O(PO4)2·(H2O)2 determined from synchrotron X-ray and neutron powder data. Eur. J. Solid State In-org. Chem. 1997, 34, 1237–1247.Chen, X.; Wang, C.; Payzant, E.; Xia, C.; Chu, D. An oxide ion and proton co-ion conducting Sn0.9In0.1P2O7 electrolyte for intermediate-temperature fuel cells. J. Electrochem. Soc. 2008, 155, B1264.
  86. Babaryk, A.A.; Adawy, A.; García, I. Trobajo, C.; Amghouz, Z.; Colodrero, R.M.P. Cabeza, A.; Olivera-Pastor, P.; Ba-zaga-García, M.; dos Santos-Gómez, L. Structural and proton conductivity studies of fibrous π-Ti2O(PO4)2·2H2O: Application in chitosan-based composite membranes. Dalton Trans. 2021, 50, 7667–7677.Kreller, C.R.; Pham, H.H.; Wilson, M.S.; Mukundan, R.; Henson, N.; Sykora, M.; Hartl, M.; Daemen, L.; Garzon, F.H. Intragranular phase proton conduction in crystalline Sn1−xInxP2O7 (x = 0 and 0.1). J. Phys. Chem. C 2017, 121, 23896–23905.
  87. Bruque, S.; Aranda, M.A.G.; R. Losilla, E.; Olivera-Pastor, P.; Maireles-Torres, P. Synthesis optimization and crystal struc-tures of layered metal(IV) hydrogen phosphates, .alpha.-M(HPO4)2.cntdot.H2O (M = Ti, Sn, Pb). Inorg. Chem. 1995, 34, 893–899.Kreller, C.R.; Wilson, M.S.; Mukundan, R.; Brosha, E.L.; Garzon, F.H. Stability and conductivity of In3+-doped SnP2O7 with varying phosphorous to metal ratios. ECS Electrochem. Lett. 2013, 2, F61−F63.
  88. Huang, W.; Komarneni, S.; Noh,Y.D.; Ma, J.; Chen, K.; Xue, D.; Xuea, X.; Jiang, B. Novel inorganic tin phosphate gel: Multi-functional material. Chem. Commun. 2018, 54, 2682–2685.Foran, G.Y.; Goward, G.R. Site-Specific Proton Dynamics in Indium-Doped Tin Pyrophosphate. J. Phys. Chem. C 2020, 124, 28407–28416.
  89. Ansari, Y.; Telpriore, G.; Tucker, C.; Angell, A. A novel, easily synthesized, anhydrous derivative of phosphoric acid for use in electrolyte with phosphoric acid-based fuel cells. J. Power Sources 2013, 237, 47–51.Scott, K.; Xu, C.; Wu, X. Intermediate temperature proton-conducting membrane electrolytes for fuel cells. Wiley Interdiscip. Rev. Energy Environ. 2014, 3, 24–41.
  90. Moshareva, M.A.; Novikova, S.A.; Yaroslavtsev, A.B. Synthesis and ionic conductivity of (NH4)1–x Hx Hf2(PO4)3 (x = 0–1) NASICON-type materials. Inorg. Mater. 2016, 52, 1283–1290.Anfimova, T.; Lie-Andersena, T.; Pristed Jensen, E.; C. Brorson Prag, C.; Nielsen, U.G.; Sørensen, D.R.; Skou, E.M.; Christensen, E.; Bjerrum, N.J.;.Li, Q. The effect of preparation method on the proton conductivity of indium doped tin pyrophosphates. Solid State Ion. 2015, 278, 209–216.
  91. Clearfield, A. Structural concepts in inorganic proton conductors. Solid State Ion. 1991, 46, 34–43.Hogarth, W.H.J.; Muir, S.S.; Whittaker, A.K.; Diniz da Costa, J.C.; Drennan, J.; Lu, G.Q. Proton conduction mechanism and the stability of sol–gel titanium phosphates. Solid State Ion. 2007, 177, 3389–3394.
  92. Clearfield, A.; Roberts, B.D.; Subramanian, M.A. Preparation of (NH4)Zr2(PO4)3 and HZr2(PO4)3. Mater. Res. Bull. 1984, 19, 219–226.Alberti, G.; Costantino, U.; Casciola, M.; Ferroni, S.; Massinelli, L.; Staiti, P. Preparation, characterization and proton conductivity of titanium phosphate sulfophenylphosphonate. Solid State Ion. 2001, 145, 249–255.
  93. Komorowski, P.G.; Agryropoulos, S.A.A.; Canaday, J.D.; Kuriakose, A.K.; Wheat, T.A.; Ahmad, A.; Gulens, J. The study of hydronium NASICON conductivity with deuterium. Solid State Ion. 1992, 50, 253–258.Zhang, L.; Liu, X.; Sun, X.; Jian, J.; Li, G.; Yuan, H. Proton conduction in organically templated 3D open-framework vanadium−nickel pyrophosphate. Inorg. Chem. 2019, 58, 4394–4398.
  94. Stenina, I.A.; Kislitsyn, M.N.; Ghuravlev, N.A.; Yaroslavtsev, A.B. Phase transitions and ionic mobility in hydrogen zirco-nium phosphates with the NASICON structure, H1 ± xZr2–xMx(PO4)3⋅H2O, M = Nb, Y. Mater. Res. Bull. 2008, 43, 377–383.
  95. Stenina, A.; Pinus, I.Y.; Rebrov, A.I.; Yaroslavtsev, A.B. Lithium and hydrogen ions transport in materials with NASICON structure. Solid State Ion. 2004, 175, 445–449.
  96. Stenina, I.A.; Zhizhin, M.G.; Lazoryak, B.I.; Yaroslavtsev, A.B. Phase transitions, structure and ion conductivity of zirconium hydrogen phosphates, H1 ± xZr2–xMx(PO4)3 ⋅ H2O (M = Nb, Y). Mater. Res. Bull. 2009, 44, 1608–1612.
  97. Mieritz, D.; Davidowski, S.K.; Seo, D. Accessing alkali-free NASICON-type compounds through mixed oxoanion sol–gel chemistry: Hydrogen titanium phosphate sulfate, H1−xTi2(PO4)3−x(SO4)x (x=0.5–1). J. Solid State Chem. 2016, 242, 116–125.
  98. Sato, Y.; Shen, Y.; Nishida, M.; Kanematsu, W.; Hibino, T. Proton Conduction in Non-Doped and Acceptor-Doped Metal Pyrophosphate (MP2O7) Composite Ceramics at Intermediate Temperatures. J. Mater. Chem. 2012, 22, 3973–3981.
  99. Singh, B.; Kima, J.-H.; Park, J.-Y.; Song, S.-J. Dense composite electrolytes of Gd3+-doped cerium phosphates for low-temperature proton-conducting ceramic-electrolyte fuel cells. Ceram. Inter. 2015, 41, 4814–4821.
  100. Nagao, M.; Kamiya, T.; Heo, P.; Tomita, A.; Hibino, T.; Sano, M. Proton conduction in In3+-doped SnP2O7 at intermediate temperatures. J. Electrochem. Soc. 2006, 153, 1604–1609.
  101. Nagao, M.; Takeuchi, A.; Heo, P.; Hibino, T.; Sano, M.; Tomita, A. A proton-conducting In3 + -doped SnP2O7 electrolyte for intermediate-temperature fuel cells. Electrochem. Solid-State Lett. 2006, 9, A105.
  102. Jin, Y.; Fujiwara, K.; Hibino, T. High temperature, low humidity proton exchange membrane based on an inorganic–organic hybrid structure. Electrochem. Solid-State Lett. 2010, 13, B8.
  103. Jin, Y.; Shen, Y.; Hibino, T. Proton conduction in metal pyrophosphates (MP2O7) at intermediate temperatures. J. Mater. Chem. 2010, 20, 6214–6217.
  104. Chen, X.; Wang, C.; Payzant, E.; Xia, C.; Chu, D. An oxide ion and proton co-ion conducting Sn0.9In0.1P2O7 electrolyte for intermediate-temperature fuel cells. J. Electrochem. Soc. 2008, 155, B1264.
  105. Kreller, C.R.; Pham, H.H.; Wilson, M.S.; Mukundan, R.; Henson, N.; Sykora, M.; Hartl, M.; Daemen, L.; Garzon, F.H. Intra-granular phase proton conduction in crystalline Sn1−xInxP2O7 (x = 0 and 0.1). J. Phys. Chem. C 2017, 121, 23896–23905.
  106. Kreller, C.R.; Wilson, M.S.; Mukundan, R.; Brosha, E.L.; Garzon, F.H. Stability and conductivity of In3+-doped SnP2O7 with varying phosphorous to metal ratios. ECS Electrochem. Lett. 2013, 2, F61−F63.
  107. Foran, G.Y.; Goward, G.R. Site-Specific Proton Dynamics in Indium-Doped Tin Pyrophosphate. J. Phys. Chem. C 2020, 124, 28407–28416.
  108. Scott, K.; Xu, C.; Wu, X. Intermediate temperature proton-conducting membrane electrolytes for fuel cells. Wiley Interdiscip. Rev. Energy Environ. 2014, 3, 24–41.
  109. Anfimova, T.; Lie-Andersena, T.; Pristed Jensen, E.; C. Brorson Prag, C.; Nielsen, U.G.; Sørensen, D.R.; Skou, E.M.; Christen-sen, E.; Bjerrum, N.J.;.Li, Q. The effect of preparation method on the proton conductivity of indium doped tin pyrophos-phates. Solid State Ion. 2015, 278, 209–216.
  110. Li, W.; Bose, A.B.; Rusakova, I.A. An approach for restoring the proton conductivity of sintered tin pyrophosphate mem-branes for intermediate temperature fuel cells. J. Power Sources 2016, 307, 146–151.
  111. Ramaiyan, K.P.; Herrera, S.; Workman, M.J.; Semelsberger, T.A.; Atanasov, V.; Kerres, J.; Sandip Maurya, S.; Kim, Y.S.; Krel-ler, C.R.; Mukundan, R. Role of phosphate source in improving the proton conductivity of tin pyrophosphate and its com-posite electrolytes. J. Mater. Chem. A 2020, 8, 16345–16354.
  112. Wu, X.; Mamlouk, M.; Scott, K. A PBI-Sb0.2Sn0.8P2O7-H3PO4 Composite Membrane. Fuel Cells 2011, 11, 620–625.
  113. Jin, Y.C.; Nishida, M.; Kanematsu, W.; Hibino, T. An H3PO4-doped polybenzimidaz-ole/Sn0.95Al0.05P2O7 composite mem-brane for high-temperature proton exchange mem-brane fuel cells. J. Power Sources 2011, 196, 6042–6047.
  114. Huang, M.; Huang, X.; Deng, Y.; Fei, M.; Xu, C.; Cheng, J. Graphite oxide-incorporated SnP2O7 solid composite electrolyte for high-temperature proton exchange membrane fuel cells. Int. J. Hydrog. Energy 2017, 42, 1113–1119.
  115. Le, M.-V.; Tsai, D.-S.; Yang, C.-Y.; Chung, W.-H.; Lee, H.-Y. Proton conductors of cerium pyrophosphate for intermediate temperature fuel cell. Electrochim. Acta 2011, 56, 6654–6660.
  116. Hogarth, W.H.J.; Muir, S.S.; Whittaker, A.K.; Diniz da Costa, J.C.; Drennan, J.; Lu, G.Q. Proton conduction mechanism and the stability of sol–gel titanium phosphates. Solid State Ion. 2007, 177, 3389–3394.
  117. Alberti, G.; Costantino, U.; Casciola, M.; Ferroni, S.; Massinelli, L.; Staiti, P. Preparation, characterization and proton con-ductivity of titanium phosphate sulfophenylphosphonate. Solid State Ion. 2001, 145, 249–255.
  118. Zhang, L.; Liu, X.; Sun, X.; Jian, J.; Li, G.; Yuan, H. Proton conduction in organically templated 3D open-framework vana-dium−nickel pyrophosphate. Inorg. Chem. 2019, 58, 4394–4398.
  119. Botez, C.E.; Tackett, R.J.; Hermosillo, J.D.; Zhang, J.; Zhao, Y.; Wang, L. High pressure synchrotron x-ray diffraction studies of superprotonic transitions in phosphate solid acids. Solid State Ion. 2012, 213, 58–62.
  120. Baranov, A.I. Crystals with disordered hydrogen-bond networks and superprotonic conductivity. Review. Crystallogr. Rep. 2003, 48, 1012–1037.
  121. Bagryantseva, I.N.; Gaydamaka, A.A.; Ponomareva, V.G. Intermediate temperature proton electrolytes based on cesium dihydrogen phosphate and Butyral polymer. Ionics 2020, 26, 1813–1818.
  122. Dreßler, C.; Sebastiani, D. Effect of anion reorientation on proton mobility in the solid acids family CsHyXO4 (X = S, P, Se, y = 1, 2) from ab initio molecular dynamics simulations. Phys. Chem. Chem. Phys. 2020, 22, 10738–10752.
  123. Taninouchi, Y.K.; Uda, T.; Awakura, Y.; Ikeda, A.; Haile, S.M. Dehydration behavior of the superprotonic conductor CsH2PO4 at moderate temperatures: 230 to 260 °C. J. Mater. Chem. 2007, 17, 3182–3189.
  124. Mathur, L.; Kim, I.-H.; Bhardwaj, A.; Singh, B.; Park, J.-Y.; Song, S.-J. Structural and electrical properties of novel phosphate based composite electrolyte for low-temperature fuel cells. Composites Part B 2020, 202, 108405.
  125. Otomo, J.; Tamaki, T.; Nishida, S.; Wang, S.; Ogura, M.; Kobayashi, T.; Wen, C.-J.; Nagamoto, H.; Takahashi, H. Effect of water vapor on proton conduction of cesium dihydrogen phosphate and application to intermediate temperature fuel cells. J. Appl. Electrochem. 2005, 35, 865–870.
  126. Uda, T.; Haile, S.M. Thin-membrane solid-acid fuel cell. Electrochem. Solid State Lett. 2005, 8, A245–A246.
  127. Navarrete, L.; Andrio, A.; Escolástico, S.; Moya, S.; Compañ, V.; Serra, J.M. Protonic Conduction of Partially-Substituted CsH2PO4 and the Applicability in Electrochemical Devices. Membranes 2019, 9, 49.
  128. Ponomareva, V.G.; Bagryantseva, I.N.; Gaydamaka, A.A. Study of the Phase Composition and Electrotransport Properties of the Systems Based on Mono- and Disubstituted Phosphates of Cesium and Rubidium. Chem. Sustain. Dev. 2019, 27, 238–245.
  129. Martsinkevich, V.V.; Ponomareva, V.G. Double salts Cs1-xMxH2PO4 (M = Na, K, Rb) as proton conductors. Solid State Ion. 2012, 225, 236–240.
  130. Ponomareva, V.G.; Bagryantseva, I.N. Superprotonic CsH2PO4-CsHSO4 solid solutions. Inorg. Mater. 2012, 48, 187–194.
  131. Ponomareva, V.G.; Uvarov, N.F.; Lavrova, G.V.; Hairetdinov, E.F. Composite protonic solid electrolytes in the CsHSO4-SiO2 system. Solid State Ion. 1996, 90, 161–166.
  132. Ponomareva, V.G.; Shutova, E.S.; Matvienko, A.A. Conductivity of Proton Electrolytes Based on Cesium Hydrogen Sulfate Phosphate. Inorg. Mater. 2004, 40, 721–728.
  133. Otomo, J.; Minagawa, N.; Wen, C.-J.; Eguchi, K.; Takahashi, H. Protonic conduction of CsH2PO4 and its composite with silica in dry and humid atmospheres. Solid State Ion. 2003, 156, 357–369.
  134. Ponomareva, V.G.; Shutova, E.S. High-temperature behavior of CsH2PO4 and CsH2PO4-SiO2 composites. Solid State Ion. 2007, 178, 729–734.
  135. Singh, D.; Singh, J.; Kumar, P.; Veer, D.; Kumar, D.; Katiyar, R.S.; Kumar, A.; Kumar, A. The Influence of TiO2 on the Proton Conduction and Thermal Stability of CsH2PO4 Composite Electrolytes. S. Afr. J. Chem. Eng. 2021, 37, 227–236.
  136. Singh, D.; Kumar, P.; Singh, J.; Veer, D.; Kumar, A.; Katiyar, R.S. Structural, thermal and electrical properties of composites electrolytes (1−x) CsH2PO4/x ZrO2 (0 ≤ x ≤ 0.4) for fuel cell with advanced electrode. SN Appl. Sci. 2021, 3, 46.
  137. Veer, D.; Kumar, P.; Singh, D.; Kumar, D.; Katiyar, R.S. A synergistic approach to achieving high conduction and stability of CsH2PO4/NaH2PO4/ZrO2 composites for fuel cells. Mater. Adv. 2021, 3, 409–417.
  138. Aili, D.; Gao, Y.; Han, J.; Li, Q. Acid-base chemistry and proton conductivity of CsHSO4, CsH2PO4 and their mixtures with N-heterocycles. Solid State Ion. 2017, 306, 13–19.
  139. Bagryantseva, I.N.; Ponomareva, V.G.; Khusnutdinov, V.R. Intermediate temperature proton electrolytes based on cesium dihydrogen phosphate and poly(vinylidene fluoride-co-hexafluoropropylene). J. Mater. Sci. 2021, 56, 14196–14206.
  140. Ponomareva, V.G.; Bagryantseva, I.N.; Shutova, E.S. Hybrid systems based on nanodiamond and cesium dihydrogen phos-phate. Mater. Today 2020, 25, 521–524.
  141. Ponomareva, V.G.; Bagryantseva, I.N. Effect of the excess protons on the electrotansport, structural and thermodynamic properties of CsH2PO4. Solid State Ion. 2017, 304, 90–95.
  142. Ponomareva, V.G.; Lavrova, G.V. The influence of Cs2HPO4·H2O impurity on the proton conductivity and thermal proper-ties of CsH2PO4. Solid State Ion. 2019, 329, 90–94.
  143. Wang, M.; Luo, H.-B.; Liu, S.-X.; Zou, Y.; Tian, Z.-F.; Li, L.; Liu, J.-L.; Ren, X.-M. Water assisted high proton conductance in a highly thermally stable and superior water-stable open-framework cobalt phosphate. Dalton Trans. 2016, 45, 19466–19472.
  144. Umeyama, D.; Horike, S.; Inukai, M.; Itakura, T.; Kitagawa, S. Inherent Proton Conduction in a 2D Coordination Frame-work. J. Am. Chem. Soc. 2012, 134, 12780–12785.
  145. Inukai, M.; Horike, S.; Chen, W.; Umeyama, D.; Itakurad, T.; Kitagawa, S. Template-directed proton conduction pathways in a coordination framework. J. Mater. Chem. A. 2014, 2, 10404–10409.
  146. Zhao, H.-R.; Xue, C.; Li, C.-P.; Zhang, K.-M.; Luo, H.-B.; Liu, S.-X.; Ren, X.-M. A Two-Dimensional inorganic−organic hybrid solid of manganese(II) hydrogenophosphate showing high proton conductivity at room temperature. Inorg. Chem. 2016, 55, 8971–8975.
  147. Phang, W.J.; Lee, W.R.; Yoo, K.; Ryu, D.W.; Kim, B.S.; Hong, C.S. PH-dependent proton conducting behavior in a met-al-organic framework material. Angew. Chem. Int. Ed. 2014, 53, 8383–8387.
  148. Nagarkar, S.S.; Unni, S.M.; Sharma, A.; Kurungot, S.; Ghosh, S.K. Two-in-one: Inherent anhydrous and water-assisted high proton conduction in a 3D metal-organic framework. Angew. Chem. Int. Ed. 2014, 53, 2638–2642.
  149. Nguyen, N.T.T.; Furukawa, H.; Gándara, F.; Trickett, C.A.; Jeong, H.M.; Cordova, K.E.; Yaghi, O.M. Three-dimensional met-al-catecholate frameworks and their ultrahigh proton conductivity. J. Am. Chem. Soc. 2015, 137, 15394–15397.
  150. Horike, S.; Chen, W.; Itakura, T.; Inukai, M.; Umeyama, D.; Asakura, H.; Kitagawa, S. Order-to-disorder structural transfor-mation of a coordination polymer and its influence on proton conduction. Chem. Commun. 2014, 50, 10241–10243.
  151. Ma, N.; Kosasang, S.; Yoshida, A.; Horike, S. Proton-conductive coordination polymer glass for solid-state anhydrous pro-ton batteries. Chem. Sci. 2021, 12, 5818–5824.
  152. Matsuda, Y.; Yonemura, M.; Koga, H.; Pitteloud, C.; Nagao, M.; Hirayama, M.; Kanno, R. Synthesis, crystal structure, and ionic conductivity of tunnel structure phosphates, RbMg1-xH2x(PO3)3y(H2O). J. Mater. Chem. A 2013, 1, 15544–15551.
  153. Antraptseva, N.M.; Solod, N.V.; Povshuk, V.A. Electrical conductivity of solid solution of Co(II)-Zn dihydrophosphate and its thermolysis products. Funct. Mater. 2015, 22, 322–326.
  154. Fan, D.; Tian, P.; Xu, S.T.; Wang, D.H.; Yang, Y.; Li, J.Z.; Wang, Q.Y.; Yang, M.; Liu, Z.M. SAPO-34 templated by dipropyla-mine and diisopropylamine: Synthesis and catalytic performance in the methanol to olefin (MTO) reaction. New J. Chem. 2016, 40, 4236–4244.
  155. Yu, Y.; Zhu, J.; Liu, J.; Yan, Y.; Song, X. Synthesis and characterization of two layered aluminophosphates [R-C8H12N]8[H2O]2·[Al8P12O48H4] and [S-C8H12N]8[H2O]2·[Al8P12O48H4] with a mirror symmetric feature and their proton conductivity. Dalton Trans. 2017, 46, 9157–9162.
  156. Park, S.H.; Choi, W.; Choi, H.J.; Hong, S.B. Organic-Free Synthesis of Silicoaluminophosphate Molecular Sieves. Angew. Chem. Int. Ed. 2018, 57, 9413–9418.
  157. Wang, Y.Y.; Sun, Y.J., Mu, Y.; Zhang, C.Q.; Li, J.Y.; Yu, J.H. Organotemplate-free hydrothermal synthesis of an alumino-phosphate molecular sieve with AEN zeotype topology and properties of its derivatives. Chem. Commun. 2014, 50, 15400–15403.
  158. Sun, Y.J.; Yan, Y.; Wang, Y.Y.; Li, Y.; Li, J.Y.; Yu, J.H. High proton conduction in a new alkali metal-templated open-framework aluminophosphate. Chem. Commun. 2015, 51, 9317–9319.
  159. Parise, J.B. Crystal Structures of Related Novel Aluminophosphate Frameworks: Aipo4-21(py), Aipo4-EN3 (en) and A Struc-tural Model for Alpo4-25. In Studies in Surface Science and Catalysis; Drzâj, S.H.B., Pejovnik, S., Eds.; Elsevier: Amsterdam, The Netherlands, 1985; Volume 24, pp. 271–278.
  160. Parnham, E.R.; Morris, R.E. The ionothermal synthesis of cobalt aluminophosphate zeolite frameworks. J. Am. Chem. Soc. 2006, 128, 2204–2205.
  161. Wei, Y.; Tian, Z.; Gies, H.; Xu, R.; Ma, H.; Pei, R.; Zhang, W.; Xu, Y.; Wang, L.; Li, K.; et al. Ionothermal synthesis of an alu-minophosphate molecular sieve with 20-ring pore openings. Angew. Chem. Int. Ed. 2010, 49, 5367–5370.
  162. Liu, L.; Yang, J.; Li, J.; Dong, J.; Šišak, D.; Luzzatto, M.; McCusker, L.B. Ionothermal sythesis and structure analysis of an open-framework zirconium phosphate with a high CO2/CH4 adsorption ratio. Angew. Chem. Int. Ed. 2011, 50, 8139–8142.
  163. Nakayama, M.; Sugiura, Y.; Hayakawa, T.; Nogami, M. A novel proton conductor of imidazole–aluminium phosphate hy-brids in the solid state. Phys. Chem. Chem. Phys. 2011, 13, 9439–9444.
  164. Wang, K.; Li, T.; Zeng, H.; Zou, G.; Zhang, Q.; Zhien Lin, Z. Ionothermal synthesis of open-framework metal phosphates using a multifunctional ionic liquid. Inorg. Chem. 2018, 57, 8726–8729.
  165. Zhang, C.; Yan, Y.; Huang, Z.; Shi, H.; Zhang, C.; Cao, X.; Jiang, J. Triclinic AlPO-34 zeolite synthesized with nicotine and its proton conduction properties. Inorg. Chem. Commun. 2018, 96, 165–169.
  166. Xue, C.; Zou, Y.; Liu, S.-X.; Ren, X.-M.; Tian, Z.-F. Two different types of channels exhibiting distinct proton transport be-haviour in an open framework aluminophosphate. J. Solid State Chem. 2018, 258, 695–701.
  167. Mu, Y.; Wang, Y.Y.; Li, Y.; Li, J.Y.; Yu, J.H. Organotemplate-free synthesis of an open-framework magnesium alumino-phosphate with proton conduction properties. Chem. Commun. 2015, 51, 2149–2151.
  168. Fan, D.; Barrier, N.; Vicente, A.; Gilson, J.-P.; Clevers, S.; Dupray, V.; Coquereld, G.; Valtchev, V. Organic template-free syn-thesis of an open framework silicoaluminophosphate (SAPO) with high thermal stability and high ionic conductivity. Inorg. Chem. Front. 2020, 7, 542–553.
  169. Zhou, D.; Chen, L.; Yu, J.H.; Li, Y.; Yan, W.F.; Deng, F.; Xu, R.R. Synthesis, crystal structure, and solid-state NMR Spectros-copy of a new open-framework aluminophosphate (NH4)2Al4(PO4)4(HPO4)·H2O. Inorg. Chem. 2005, 44, 4391–4397.
  170. Zhao, H.R.; Jia, Y.; Gu, V.; He, F.Y.; Zhang, K.M.; Tian, Z.F.; Liu, J.L. A 3D open-framework iron hydrogenophosphate showing high proton conductance under water and aqua-ammonia vapor. RSC Adv. 2020, 10, 9046–9051.
  171. Zima, V.; Lii, K.-H. Synthesis and characterization of a novel one-dimensional iron phosphate: [C4H12N2]1.5[Fe2(OH)(H2PO4)(HPO4)2(PO4)]·0.5H2O. J. Chem. Soc. Dalton Trans. 1998, 24, 4109–4112.
  172. Lii, K.-H.; Huang, Y.-F. Large tunnels in the hydrothermally synthesized open-framework iron phosphate (NH3(CH2)3NH3)2[Fe4(OH)3(HPO4)2(PO4)3]·xH2O. Chem. Commun. 1997, 9, 839–840.
  173. Bazaga-García, M.; Colodrero, R.M.P.; Papadaki, M.; Garczarek, P.; Zon, J.; Olivera-Pastor, P.; Losilla, E.R.; Reina, L.L.; Aranda, M.A.; Choquesillo-Lazarte, D.; et al. Guest Molecule-Responsive Functional Calcium Phosphonate Frameworks for Tuned Proton Conductivity. J. Am. Chem. Soc. 2014, 136, 5731–5739.
  174. Lim, D.-W.; Kitagawa, H. Proton Transport in Metal−Organic Frameworks. Chem. Rev. 2020, 120, 8416–8467.
  175. Mamlouk, M.; Scott, K. A boron phosphate-phosphoric acid composite membrane for medium temperature proton ex-change membrane fuel cells. J. Power Sources 2015, 286, 290–298.
  176. Pusztai, P.; Haspel, H.; Tóth, I.Y.; Tombácz, E.; László, K.; Kukovecz, Á.; Kónya, Z. Structure-Independent Proton Transport in Cerium(III) Phosphate Nanowires. ACS Appl. Mater. Interfaces 2015, 7, 9947–9956.
  177. Petersen, H.; Stefmann, N.; Fischer, M.; Zibrowius, I.R.; Philippi, W.; Schmidt, W.; Weidenthaler, C. Crystal structures of two titanium phosphate-based proton conductors: Ab initio structure solution and materials properties. Inorg. Chem. 2022, 61, 2379–2390.
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