Hierarchically porous Co3O4 architectures with honeycomb-like structures for efficient oxygen generation from electrochemical water splitting

Abstract The development of efficient and cheap anode materials for the utilization in the oxygen evolution reaction (OER) is essential for energy-conversion technologies. In this study, hierarchically porous Co 3 O 4 architectures with honeycomb-like structures are synthesized by employing cobalt-based zeolitic imidazolate framework (ZIF-67-Co) as metal source and sacrificial template. After a simple one-step calcination process, the ZIF-67-Co precursor can be chemically transformed into the Co 3 O 4 architectures with abundant porosity and oxygen vacancy. These easily obtained and earth-abundant Co 3 O 4 architectures present high performance toward the electrochemical water splitting for evolving molecular oxygen, affording a small OER onset potential, large anodic current and long-term durability in 0.1 M KOH solution, which are comparable to the electroactive noble- and transition-metal oxygen evolution catalysts previously reported. These merits suggest that the ZIF-derived Co 3 O 4 architectures are promising electrocatalysts for OER from water splitting.