Local supermetastable active structure via electrochemical reconstruction toward electrooxidation process

摘要

The reconstruction of metastable materials in the electrocatalytic process brings difficulties to the determination of the relationship of structure to activity, but it also brings hope for new active structures of catalysts. Grasping the reconstruction rule of the meta-stable materials and further constructing the local supermetastable active structure artificially are essential for clarifying the nature of catalysis and breaking the bottleneck of catalytic activity. Herein, we used a hierarchical structural CoMoO4/Ni(OH)2 as a precursor to construct a local supermetastable active structure CoOOH(Mo)/ NiOOH via an electrochemical reconstruction strategy. Based on in situ electrochemical XAS and Raman spectroscopy, combined with XPS and DFT calculations, the reconstruction process and the mechanism of electrocatalytic urea oxidation were explored in detail. The improved electrocatalytic activity, stability, and selectivity of CoOOH(Mo)/NiOOH can be attributed to the synergy between Ni(III), Co(III), and high-valence Mo. This research paves the way for the rational design and synthesis of catalysts to achieve energy conversion.