Lanthanum oxide rods as a novel and efficient bifunctional hydrogen and oxygen evolution electrocatalyst for overall water splitting

Abstract

Novel and efficient catalytic materials with enhanced electrocatalytic properties are needed for hydrogen production from water through electrochemical water splitting. In this study, novel lanthanum oxide rods were prepared using a facile, soft chemical process. These lanthanum oxide rods were used for electrocatalytic hydrogen and oxygen evolution reactions. Electrochemical studies of the catalyst at 100 mA cm−2 indicated overpotentials of ∼340 and ∼405 mV for hydrogen and oxygen evolution reactions, respectively. In addition, the lanthanum oxide rods demonstrated good stability. Finally, lanthanum oxide rods were used as the cathode and anode to fabricate the electrolyzer in a two-electrode configuration. This electrolyzer required 1.6 V to drive 10 mA cm−2, and its performance did not change significantly during durability testing. To the best of our knowledge, this is the first study demonstrating the use of lanthanum oxide rods in electrocatalysis. The prepared lanthanum oxide rods have good electrocatalytic activity, and therefore, they are promising materials for the development of alkaline electrolyzers.