Hydrogen uptake by barium manganite at atmospheric pressure

Abstract

Investigation of the interaction of hydrogen with alkaline earth manganites (IV) AMnO 3 (A = Ca, Sr, Ba), dispersed with 1 at.% Pt, has revealed an unprecedented uptake of hydrogen by BaMnO 3/Pt to the extent of ∼1.25 mass% at moderate temperatures (190–260 °C) and ambient pressure. Gravimetric sorption isotherms and mass spectrometric analysis of the desorption products indicate that approximately three hydrogen atoms per mol of BaMnO 3/Pt is inserted reversibly. The nature of hydrogen in the insertion product, BaMnO 3H 3, is discussed. The work suggests the possibility of developing new hydrogen storage materials based on electropositive metal–transition metal–oxide systems.