Perspectives of neutron scattering on proton conducting oxides.

Understanding the fundamental properties of materials of relevance for alternative energy technologies is crucial in addressing the global challenge of cleaner sources of energy. This Perspective article aims to demonstrate the important role that neutron scattering now plays in advancing the state of the art of the basic understanding of proton conducting oxides, which show potential as electrolytes in next-generation intermediate temperature fuel cells. In particular, the breadth of neutron scattering work on perovskite structured oxides, which continue to be the most promising class of electrolytes for intermediate-temperature applications, is reviewed. Key fundamental properties that are addressed include structures, proton sites, hydrogen-bonding interactions, proton dynamics, and concentration of protons in materials. Furthermore, the perspectives for future neutron studies within this field of research are discussed.