A simple method of growth and lithiation of Ba6Mn24O48 whiskers

Abstract

Isothermal crystal growth from evaporating fluxes of alkaline chlorides allowed the reproducible, high yield synthesis of micron thick and millimetre long whiskers of two manganese-rich phases, BaMn₈O₁₆ hollandite and Ba₆Mn₂₄O₄₈ manganite, with a tunnel crystal structure. The crystal morphology suggests that they grow by a VLS (vapour–liquid–solid)-related mechanism. An ion exchange in molten LiNO₃ at about 300 °C was found to introduce lithium in structural channels of the Ba₆Mn₂₄O₄₈ phase due to partial barium substitution.