What is the purpose of https energy technology

SENTECH Rare earth nickelates for future energy technologies

#853538

Oxide ceramics with high oxygen and hydrogen ion conductivity, high electronic conductivity and high catalytic activity offer a number of future application possibilities in the energy sector, such as electrodes in high-temperature fuel and electrolysis cells, ceramic membranes for selective oxygen or hydrogen separation, electrochemical oxygen or hydrogen sensors and heterogeneous catalysts. Rare earth nickelates An + 1B.nO3n + 1 (A = La, Pr, Nd; B = Ni; n = 1,2,3 etc.) have one of the highest currently known diffusivities and ionic conductivities for oxygen with good electronic conductivity at the same time. By substituting these compounds on the A and B grid positions, it is possible to vary their material properties in a targeted manner. A prerequisite for this, however, is a deeper understanding of the mass and charge transport properties, defect chemistry and structure-property relationships of the new compounds, which are still little researched. There are hardly any studies, especially on the suspected proton conductivity in these materials.

In the project at hand, promising new compositions of A- and B-position substituted rare earth nickelates are produced on the basis of structural-chemical considerations and characterized in terms of structure-property relationships. MUL focuses on the synthesis of materials and their characterization with regard to phase purity, oxygen non-stoichiometry, oxygen exchange kinetics and ionic or electronic conductivity. MPI supplements these activities with the experimental determination of the oxygen and hydrogen exchange properties on thin-film electrodes and the elucidation of the underlying reaction mechanisms. The jointly developed results of the MUL and MPI are incorporated into the creation of defect chemical models for the new materials, whereby H-defects are also taken into account for the first time in addition to the electronic species and O-defects. The ZFE enables the correlation of the mass and charge transport properties investigated by MUL and MPI with the microstructural properties through accompanying analyzes using high-resolution scanning transmission electron microscopy (STEM). Among other things, in-situ TEM analyzes to elucidate atomic structural changes due to changes in the oxygen content of new rare earth nickelates will be carried out for the first time as part of this work. As a result of the project, a knowledge base will be created which will make it possible in the future to predict the mode of action of targeted substitution on the structural and transport properties of rare earth nickelates and to develop new materials for future applications in the energy sector.

initial situation

Mixed conductive materials with high oxygen and hydrogen ion conductivity, high electronic conductivity and high catalytic activity offer a number of future application possibilities in the energy sector, such as electrodes in high-temperature fuel and electrolysis cells, ceramic membranes for selective oxygen or hydrogen separation, electrochemical oxygen resp. Hydrogen sensors and heterogeneous catalysts. Rare earth nickelates have one of the highest currently known diffusivities or ionic conductivities for oxygen with good electronic conductivity at the same time. The mass and charge transport properties, defect chemistry and structure-property relationships, especially of the new A- and B-position substituted Ruddlesden-Popper phases, have not yet been researched. There are hardly any scientific studies, especially on the suspected proton conductivity in these materials.