Hydrogen uptake by barium manganite at atmospheric pressure

Investigation of the interaction of hydrogen with alkaline earth manganites (IV) AMnO3 (A = Ca, Sr, Ba), dispersed with 1 at.% Pt, has revealed an unprecedented uptake of hydrogen by BaMnO3/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 BaMnO3/Pt is inserted reversibly. The nature of hydrogen in the insertion product, BaMnO3H3, is discussed. The work suggests the possibility of developing new hydrogen storage materials based on electropositive metal–transition metal–oxide systems.