Proton conduction of Ba6Mn24O48 tunnel manganite

A protonated Ba6Mn24O48 phase with an original tunnel crystal structure and mixed-valent manganese has been prepared in the form of powders and millimeter-long fibrous crystals (whiskers). A combined study either by impedance spectroscopy or transport measurements revealed that the Ba6Mn24O48 phase demonstrates mixed conductivity with both proton and electronic components reaching ∼ 10− 3 Ω− 1∙cm− 1 at room temperature.