Amorphous MOF Introduced N-Doped Graphene: An Efficient and Versatile Electrocatalyst for Zinc-Air Battery and Water Splitting

Recently, developing metal-organic framework (MOF) derived carbon-based electrocatalysts has become more and more popular for large-scale application of renewable energy devices. However, the rational conversion of MOFs into a versatile platform for high-efficiency catalyst is still very challenging. Moreover, the relationship between the crystallinity of MOF precursor and the catalytic activity of resultant carbon-based catalyst is still not well-understood. In this work, a strategy for the synthesis of sheet-like mesoporous nitrogen-doped graphene (MNG) derived from amorphous MOFs is demonstrated. The amorphous MOF derived MNG showed much higher catalytic activity than that of nitrogen-doped carbon (MNC) derived from highly crystallized MOFs. This rationally designed MNG catalyst served as a multifunctional electrode in a zinc-air battery and a water splitting device, both of which showed electrocatalytic performance superior to those of platinum group metal (PGM) catalysts. The characterization analysis confirmed that the enhanced activity of amorphous MOF derived MNG was primarily attributed to the optimal properties of electronic conductivity, graphitization degree, and high specific surface area.