TY - JOUR

T1 - Rb5H7(PO4)4 as a new example of the superprotonic conductor

AU - Gaydamaka, Anna A.

AU - Ponomareva, Valentina G.

AU - Bagryantseva, Irina N.

N1 - Publisher Copyright: © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.

PY - 2019/2/5

Y1 - 2019/2/5

N2 - Thermal and transport properties, as well as spectral characteristics of Rb5H7(PO4)4, have been investigated by several methods. It was shown that Rb5H7(PO4)4 undergoes a reversible phase transition at Tp ~ 237 °С. However, the interval of the high-temperature phase stability is quite narrow, about 15 °С. The initial dehydration event in Rb5H7(PO4)4 occurs at 200 °С. The conductivity measurements were performed under highly humidified conditions (PH2O ≈ 0.56 atm.) to suppress dehydration of the title salt. The phase transition leads to the sharp increase of proton conductivity up to 10−2 S/cm. The reverse transition goes slowly with significant hysteresis on cooling. Thus, the superprotonic conductivity of Rb5H7(PO4)4 was determined. The possibility of superionic phase stabilization by humidification was shown. The IR- and Raman spectra have been recorded at room temperature and discussed in relation to the crystal structure.

AB - Thermal and transport properties, as well as spectral characteristics of Rb5H7(PO4)4, have been investigated by several methods. It was shown that Rb5H7(PO4)4 undergoes a reversible phase transition at Tp ~ 237 °С. However, the interval of the high-temperature phase stability is quite narrow, about 15 °С. The initial dehydration event in Rb5H7(PO4)4 occurs at 200 °С. The conductivity measurements were performed under highly humidified conditions (PH2O ≈ 0.56 atm.) to suppress dehydration of the title salt. The phase transition leads to the sharp increase of proton conductivity up to 10−2 S/cm. The reverse transition goes slowly with significant hysteresis on cooling. Thus, the superprotonic conductivity of Rb5H7(PO4)4 was determined. The possibility of superionic phase stabilization by humidification was shown. The IR- and Raman spectra have been recorded at room temperature and discussed in relation to the crystal structure.

KW - Ac-impedance spectroscopy

KW - Proton conductivity

KW - RbH(PO)

KW - Superprotonic conductors

KW - Thermal analysis

KW - RBH2PO4

KW - HIGH-TEMPERATURE

KW - CSH2PO4

KW - Rb5H7(PO4)(4)

KW - COMPOSITE

KW - DEHYDRATION BEHAVIOR

UR - http://www.scopus.com/inward/record.url?scp=85058849130&partnerID=8YFLogxK

U2 - 10.1007/s11581-018-2833-7

DO - 10.1007/s11581-018-2833-7

M3 - Article

AN - SCOPUS:85058849130

VL - 25

SP - 551

EP - 557

JO - Ionics

JF - Ionics

SN - 0947-7047

IS - 2

ER -