Investigation of the catalytic activity of LaBO3 (B = Ni, Co, Fe or Mn) prepared by the microwave-assisted method for hydrogen evolution in acidic medium

LaBO3 (B = Ni, Co, Fe and Mn) were prepared by microwave-assisted citrate method. The electrocatalytic activity toward hydrogen evolution reaction (HER) was investigated. XRD characterization showed that pure perovskite crystals were indeed formed. SEM images showed that changing the type of the B-site metal ion affected the morphology of the prepared perovskites. The influence of the type of B-cation on the catalytic activity toward hydrogen evolution was studied and the order of the electrocatalytic activity was LaFeO3 > LaCoO3> LaNiO3 > LaMnO3, that was related to the calculated values of the activation energy 51.61, 45.37, 41.15 and 55.05 kJ mol(-1) for LaBO3 (B = Ni, Co, Fe and Mn), respectively. The reaction order and the reaction mechanism for all the prepared perovskites were identified. In addition, the effect of the partial substitution at the B-site in LaNi1-xCoxO3 was also studied. It was found that among ternary perovskites, the catalytic activity of LaNiO3 decreased by increasing the fraction of doped-Co. (C) 2011 Elsevier Ltd. All rights reserved.