A Heavily Substituted Manganite in an Ordered Nanocomposite for Long-Term Energy Applications

The implementation of nano-engineered composite oxides opens up the way towards the development ofa novel class of superior energy materials. Vertically aligned nanocomposites are characterized by acoherent, dense array of vertical interfaces, which allows for the extension of local effects to the wholevolume of the material. Here, we use such a unique architecture to fabricate highly electrochemicallyactive nanocomposites of lanthanum strontium manganite and doped ceria with unprecedented stabilityand straight applicability as functional layers in solid state energy devices. Direct evidence of synergisticlocal effects for enhancing the electrochemical performance, stemming from the highly ordered phasealternation, is given here for the first time using atom-probe tomography combined with oxygen isotopicexchange. Interface-induced cationic substitution, enabling lattice stabilization, is presented as the originof the observed long-term stability. These findings reveal a novel route for materials nano-engineeringbased on the coexistence between local disorder and long-range arrangement.