Understanding the key role of the surface structure of L11-ordered PtCu intermetallic electrocatalyst toward methanol oxidation reaction by dealloying methods

作者：Xu, Kaiyang; Liang, Lecheng; Pan, Jiajie; Li, Keke; Zeng, Binwen; Cui, Zhiming^*; Liu, Quanbing^*

来源：Applied Surface Science, 2023, 618: 156573.

DOI：10.1016/j.apsusc.2023.156573

• Electrocatalysis
• Methanol oxidation reduction
• Intermetallic
• Dealloying

An accurate understanding of the surface structure-activity relationship is essential to rational designing highly efficient electrocatalysts for methanol oxidation reaction (MOR). Here, L1(1)-ordered PtCu/C with rough and smooth Pt shells were obtained by electrochemically (ED) and chemically dealloying (CD) methods to investigate the difference in their MOR performances. The rough Pt shells (PtCu/C-700-ED) exhibited mass activity (MA) of 1625.2 mA mg(Pt)(-1) at peak potential, 2.19 and 2.74 times higher than smooth Pt shells (PtCu/C-700-CD) (743.1 mA mg(Pt)(-1)) and commercial Pt/C (593.5 mA mg(Pt)(-1)), respectively. DFT calculations indicate that PtCu with rough surfaces has a weaker CO binding energy than that with smooth surfaces, leading to better CO resistance and MOR activity. However, accelerated durability tests exhibit that the PtCu/C-700-CD catalysts obtained activity above the initial current density after 2000 cycles compared to PtCu/C-700-ED (36.48% loss) and commercial Pt/C (67.35% loss), indicating that smooth Pt shells have prominent structural stability. In addition, similar results were found simultaneously for other ordered Pt-based binary catalysts.

• 单位
  广东工业大学