摘要
Composite coatings of Ni Co LaNi5, prepared by electrolytic codepositon of Ni Co alloys and LaNi5 particles from a sulfamate electrolyte were investigated in view of its possible application as electrocatalytic materials for the hydrogen evolution reaction(HER). The surface morphology and microstructure of Ni Co LaNi5 coatings were observed by means of SEM and XRD. Electrocatalytic efficiency was evaluated on the basis of electrochemical steady state Tafel polarization and electrochemical impedance spectroscopy technology in 1mol· L- 1 NaOH solution. The results were compared with Ni Co and Ni electrodes. The real electrochemical area was estimated by apparent double layer capacitances to account for the large difference in roughness factor of the three surfaces. The values obtained for the apparent energy of activation were 32.48kJ· mol- 1,46.29kJ· mol- 1 and 57.03kJ· mol- 1 for the HER on the Ni Co LaNi5, Ni Co and Ni electrodes, respectively. The composite coatings Ni Co LaNi5 is catalytically more active than Ni and Ni Co electrodes due to the increase in its real surface areas and the decrease in the apparent energy of activation caused by electrocatalytic synergistic effect of the Ni Co alloy and the rare earth compound on the electrode surface.
Composite coatings of Ni-Co-LaNi5, prepared by electrolytic codepositon of Ni-Co alloys and LaNi5 particles from a sulfamate electrolyte were investigated in view of its possible application as electrocatalytic materials for the hydrogen evolution reaction(HER). The surface morphology and microstructure of Ni-Co-LaNi5 coatings were observed by means of SEM and XRD. Electrocatalytic efficiency was evaluated on the basis of electrochemical steady-state Tafel polarization and electrochemical impedance spectroscopy technology in 1mol . L-1 NaOH solution. The results were compared with Ni-Co and Ni electrodes. The real electrochemical area was estimated by apparent double-layer capacitances to account for the large difference in roughness factor of the three surfaces. The values obtained for the apparent energy of activation were 32. 48kJ . mol(-1), 46. 29kJ . mol(-1) and 57. 03kJ . mol(-1) for the HER on the Ni-Co-LaNi5, Ni-Co and Ni electrodes, respectively. The composite coatings Ni-Co-LaNi5 is catalytically more active than Ni and Ni-Co electrodes due to the increase in its real surface areas and the decrease in the apparent energy of activation caused by electrocatalytic synergistic effect of the Ni-Co alloy and the rare-earth compound on the electrode surface.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2003年第7期739-744,共6页
Chinese Journal of Inorganic Chemistry
基金
山东省科技发展计划基金资助项目(No.2002014)。
