Optimization of the synthesis conditions for LaNiO 3 catalyst by microwave assisted citrate method for hydrogen production

Abstract

LaNiO 3 was prepared by microwave assisted citrate method. The effect of the synthesis condition such as, the operating microwave power and the microwave irradiation time, on structural, surface and catalytic properties was investigated by XRD, SEM, Tafel linear polarization and impedance measurements. The XRD results suggested successful incorporation of Ni 3+ at the La 3+ cations sites confirming the formation of the hexagonal distorted rhombohedral perovskite phase of LaNiO 3 at all the investigated microwave operating powers and irradiation times. The average particle size ranges between 18 and 32 nm. The largest surface area ( ca. 25 m 2 g −1) and the highest catalytic activity for LaNiO 3 prepared by the microwave assistant-citrate method toward the hydrogen evolution reaction (HER) were obtained at an operating microwave power of 720 W and increased by increasing the microwave irradiation time. In addition, the reaction order, the activation energy and the reaction mechanism were identified.