Proton conductivity of Al(H2PO4)3–H3PO4 composites at intermediate temperature

Conductivity of a new pyrophosphate Sn0.9Sc0.1(P2O7)1−δ prepared by an aqueous solution method

“…In a recent report, we have found that addition of only 0.7 mol% excess of H 3 PO 4 can increase the conductivity of solid acid Al(H 2 PO 4 ) 3 by three orders of magnitude [27]. Recently the proton conductivity of mesoporous SiP 2 O 7 and SiP 2 O 7 -H 3 PO 4 has been reported [28].…”

A stable NH4PO3-glass proton conductor for intermediate temperature fuel cells

“…PTFE bonded carbon (Carbot Vulcan XC-72R) was dabbed on both sides of the pellets which served as electrodes. Carbon paper (Torory TGPH-090) was subsequently pressed on as current collector [19]. The impedance spectra were recorded after holding one hour at each temperature to reach equilibrium by using a 4-electrode technique.…”

“…Intermediate temperature fuel cells (150-550°C), which combine most of the advantages and avoid a number of the disadvantages of both high and low temperature systems, are attracting increasing attention nowadays [1][2][3][4][5][6][7]. They show great potentials to solve the problems existing in the high and/or low temperature fuel cells, such as the CO poisoning of Pt catalyst for proton exchange membrane fuel cells or materials degradation for solid oxide fuel cells [8].…”

“…Therefore, the high conductivity of CsH 2 PO 4 is only achieved in the small temperature range between 230°C and 260°C. Moreover, high pressure or humidity is required to keep the highly conductive CsH 2 PO 4 phase stable [1][2][3][4][5][6][7][8][9]15]. Durability could be an issue for CsH 2 PO 4 -based materials for practical applications.…”

Anhydrous proton-conducting organic–inorganic hybrid membranes synthesized from tetramethoxysilane/methyltrimethoxysilane/diisopropyl phosphite and ionic liquid

“…Therefore, in recent years there has been a great deal of research in the development of anhydrous electrolyte membranes with high proton conductivities at temperatures above 100°C [11][12][13][14][15]. Electrolyte membranes based on inorganic acids (e.g., H 3 PO 4 or HPAs) have shown high proton conductivity at elevated temperatures, but their high chemical activity and thermal instability are main drawbacks for practical fuel cell applications [16][17][18]. Recently, polybenzimidazole (PBI)-phosphoric acid (H 3 PO 4 )-based membranes were reported as most prominent electrolytes for high temperature proton exchange membrane fuel cells due to the polymer rigidity and "phosphophilicity" (solubility or affinity for phosphoric acid) [19][20][21][22][23][24].…”