Crystalline–amorphous Co@CoO core–shell heterostructures for efficient electro-oxidation of hydrazine

Abstract

Metal–metal oxide core–shell heterostructures have exhibited outstanding performances in many realms, especially in catalysis, due to enriched phase interfaces and strong metal/metal oxide interactions. Herein, Co@CoO core–shell heterostructures with a crystalline Co core and an amorphous CoO shell have been prepared using a simple solution reduction process and shown to be effective catalysts for the electro-oxidation of hydrazine in alkaline media. The synergistic effect between the crystalline metallic Co core and the amorphous CoO shell leads to a small onset potential of −1.10 V vs. Ag/AgCl. In addition, the Co@CoO electrode has been shown to exhibit good long-term catalytic stability.