Amaru González Pereira, María Teresa Fernández-Díaz, Laura Pascual, Maria Retuerto, José Antonio Alonso, José Luis García Fierro, Sergio Rojas, Miguel A. Peña, Francisco J. Pérez-Alonso, Consejo Superior de Investigaciones Científicas (España), Sociedad Española de Catálisis, Comunidad de Madrid, and Ministerio de Economía y Competitividad (España)
LaNiO perovskite is a promising electrocatalyst for the oxygen reduction reaction (ORR). In this work we study the effects of several key structural and morphological features on the performance of LaNiO perovskites for the ORR. We have prepared a series of LaNiO oxides via soft chemistry and calcined the final materials at different temperatures from 500 to 1000 °C. With the aim of obtaining morphological and structural information relevant to their performance the prepared oxides have been thoroughly characterized by BET, Power Neutron Diffraction (PND), XRD, HRTEM, STEM-HAADF and XPS. We have analysed the effect of extrinsic (surface area and particle size) and intrinsic factors (formation of oxygen vacancies, Ni oxidation states and occupancy of the e levels) on the current densities and specific activity, respectively, of several samples of LaNiO. The catalysts with higher catalytic activity are those in which the perovskite structure is properly formed, but display high surface areas., María Retuerto acknowledges the Juan de la Cierva program of the Spanish Ministry of Economy and Competitiveness for a grant (FPDI-2013-17582). Economic support from projects ENE2013-42322-R from the Spanish Ministry of Economy and Competitiveness, and project 201480E122 from the CSIC are also acknowledged. Project S2013/MAE-2882 is also acknowledged. J. A. Alonso and M. Teresa Fernández-Diaz thank the financial support of the Spanish Ministry of Science and Innovation to the project MAT2013-41099-R. Amaru González acknowledges the SECAT for a grant.