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 similar to 1.25 mass% at moderate temperatures (190-260 degreesC) 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-transitionmetal-oxide systems.