Realizing a Lattice Se Atom-Modified Co Hydroxide Catalyst via Electrochemical Reconstruction for Enhanced Oxygen Evolution Performance

The lattice Se atom-modified CoOOH electrocatalystwas predictedto exhibit an ideal performance toward the oxygen evolution reactionwith a lower energy barrier of the rate-determining step. Experimentalevidence demonstrates that the lattice-modified CoOOH could be obtainedby the electrochemical reconstruction of the Co0.85Se precatalyst,which displays superior OER activity, consistent with the theoreticalprediction. Realizing a highly efficient oxygen evolution reaction(OER) processis of great significance for hydrogen energy development. The mainchallenge still lies in fabricating superior electrocatalysts withfavorable performance. Constructing electrocatalysts with ingeniouslattice modifications is a considerable way for the rational designof highly active catalytic centers. Here, theoretical calculationspredict that the lattice incorporation of Se atoms can effectivelyenhance the reaction activity of OER with a decreased energy barrierfor the rate-determining step. To obtain the corresponding desiredelectrocatalyst, the optimized lattice Se-modified CoOOH, with theideal OER performance of low overpotential and stability, was delicatelydesigned and fabricated by the electrochemical activation of the Co0.85Se precatalyst. X-ray absorption spectroscopy (XAS) demonstratesthat lattice incorporation is more likely to be generated in Co0.85Se compared to CoSe2 and CoO precatalysts, whichpromoted the subsequent OER process. This work clarified the correlationbetween the precatalyst and the lattice-modified final catalyst inconnection with electrochemical reconstruction.

Automated summary

The lattice Se atom-modified CoOOH electrocatalyst with a lower energy barrier was obtained through the electrochemical reconstruction of the Co0.85Se precatalyst, and it exhibited superior oxygen evolution reaction (OER) activity, which was consistent with theoretical predictions. Designing and fabricating electrocatalysts with ingenious lattice modifications are crucial for achieving a highly efficient OER process.