Nb提升Co基酸性析氧电催化剂活性OA

Development of efficient and stable non-precious metal catalysts is crucial for proton exchange membrane(PEM)water electrolysis.Although Co-based catalysts typically exhibit high electrocatalytic activity,their activity and stability in acidic conditions still lag behind noble metal catalysts(Ir or Ru).This study enhances the electrocatalytic performance of Co3O4 through Nb ion doping.Compared with undoped Co3O4,Co3Nb0.2 demonstrates a significantly negative shift in onset potential and shows an overpotential of only 463 mV at 10 mA/cm2 current density.Furthermore,Co3Nb0.2 exhibits substantially improved stability relative to Co3O4.X-ray diffraction patterns,electrochemical active surface area analysis,and electrochemical impedance spectroscopy reveal that minor Nb doping preserves the spinel crystal structure of Co3O4 while effectively increasing its electrochemical active surface area and reducing charge transfer resistance,which constitute the primary reasons for the enhanced electrocatalytic performance of Co3Nb0.2.