Date of Award

2017-01-01

Degree Name

Master of Science

Department

Physics

Advisor(s)

Cristian E. Botez

Abstract

We have used single-crystal X-ray diffraction measurements to investigate the structural modifications induced by Rb-doping of the protonic conductor CsH2PO4. Data collected on the RbxCs 1-xH2PO4 (0 ≤ x ≤ 1) series shows that the monoclinic P21/m CsH2PO4 presentation persists upon Rb-doping up until x = 0.8. Rb0.8Cs0.2H2PO 4 exhibits a previously unreported P21/c monoclinic structure, where the mirror plane is lost and disorder is present in the PO4 tetrahedra even at room temperature. Higher levels of x display a tetragonal I-42d unit cell isomorphic with the known structure of RbH2PO 4. The temperature dependence of the proton conductivity determined from impedance spectroscopy data collected within the 160°C–250°C range is also markedly different at high Rb-doping levels, x = 0.8. Finally, Rb0.9Cs0.1H2PO4 undergoes a transition from its room-temperature tetragonal I-42d phase to an intermediate-temperature monoclinic P21/m modification at a significantly lower temperature (~80 °C) than pure RbH2PO4 (~120 °C).

Language

en

Provenance

Received from ProQuest

File Size

70 pages

File Format

application/pdf

Rights Holder

Andres Jose Encerrado Manriquez

Included in

Physics Commons

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