Boosting the Oxygen Evolution Electrocatalysis Performance of Iron Phosphide via Architectural Design and Electronic Modulation

Developing high-performance and earth-abundant electrocatalysts for the oxygen evolution reaction (OER) is vital to renewable energy conversion systems. Herein, we have developed a facile approach to nanoscale Co-doped iron phosphide (CoFe-P) with spindle-like morphology via topological conversion of a bimetallic metal-organic frameworks (MOF). It is found that the morphology of nanospindle together with Co-doping induced downsizing is beneficial for the increase of electrochemical active surface area to expose more active centers for catalysis and, meanwhile, promoting mass transportation. Significantly, incorporation of Co species in Fe-P host can favorably modulate the local electronic structure of the electrocatalytic active sites, giving rise to enhanced intrinsic activity. Consequently, the spindle-like Co engineered Fe-P presents remarkable OER performance, making it on par with the state-of-the-art OER catalysts reported so far. Impressively, this approach is versatile; other transition metals such as Mn, Ni, Cu, La, and Ce can be doped into the Fe-P host to achieve tunable electrocatalytic activities. This work not only provides a cost-effective advanced Fe-based electrocatalyst by Co doping but also highlights that the rational architectural design and electronic modulation is an effective protocol to significantly boost performance of the electrocatalysts for future renewable energy technologies.