Lattice Strain Facilitated Oxygen Vacancy Migration in LaFe_0.2Ni_0.8O₃for Electrocatalytic Amine Coupling

Lattice distortion exerts a direct influence on the concentration of active oxygen species and the migration of oxygen vacancies, thereby indirectly modulating the efficiency of energy conversion and utilization in electrocatalytic reactions. This study investigates the mechanism by which B-site Fe doping in LaFe_0.2Ni_0.8O₃ confers high selectivity in the electrocatalytic dehydrogenative coupling of amines. Fe doping broadens the operating potential window and facilitates the formation of FeOOH species at low potentials, thereby providing additional active sites and enhancing electrical conductivity through Ni–Fe synergistic effects. Moreover, Fe doping induces local electronic restructuring of the Ni (Fe)-O bonds and significantly reduces the migration energy barrier of oxygen vacancies. The lowest barrier, merely 0.38 eV, is achieved when migration occurs along the vertical pathway via Ni–Fe dual sites. DFT calculations reveal that the incorporation of Fe significantly reduces the energy barrier for the initial dehydrogenation step of the *NH₂ intermediate. The successful synthesis of six energetic azo compounds further demonstrates the broad applicability of this strategy.