Stabilizing Ni atoms on PtNi crystals by constructing PtNix-(CeO2)y heterostructures for improving durability of oxygen reduction reaction in acidic media. Issue 2 (April 2023)

• Record Type: Journal Article
• Authors: Wang, Haibin; Meng, Fanchao; Dou, Di; Bao, Lixia; Zhao, Qiuping; Li, Chuilei; Wang, Yi; Cong, Yuanyuan
• Is Part Of: Journal of environmental chemical engineering. Volume 11:Issue 2(2023)
• Publication Date: 2023-04
• Subjects: Oxygen reduction reaction -- PtNi-CeO2 heterostructure -- Activity -- Durability; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2023.109492
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: The oxygen reduction reaction (ORR) activity of PtNi alloys is easily decreased on account of the Ni leaching under the harsh acidic environment. Therefore, we prepared a PtNi1.5 -(CeO2 )0.8 /C electrocatalyst with abundant PtNi1.5 -(CeO2 )0.8 interfaces by a wet-chemical synthesis strategy. Electrochemical tests revealed that PtNi1.5 -(CeO2 )0.8 /C exhibits excellent ORR performance with mass activity (MA) of 551.1 mA mgPt −1 and specific activity (SA) of 1.3 mA cmPt −2 @ 0.9 V vs. RHE, respectively, which are better than commercial JM Pt/C (MA of 152.9 mA mgPt −1 and SA of 0.2 mA cmPt −2 @ 0.9 V vs. RHE). More interestingly, it displays remarkable durability with 9.0% of its initial MA loss after 10, 000 CV cycles, outperforming JM Pt/C (a 15.1% loss) and PtNi1.5 /C counterparts (a 35.5% loss). The density functional theory (DFT) calculations explained that the electronic interaction at interfaces leads to a lower d -band center ( ε d ) and weaker oxygen adsorption energy E (ads) (O) in Pt atoms of PtNi1.5 -(CeO2 )0.8 than that in Pt NPs, which is favorable for the desorption of O* and promotes the ORR process. Furthermore, the diffusion energy barrier E (FS-IS) of Ni atoms in PtNi1.5 -(CeO2 )0.8 from subsurface to surface is higher than that in PtNi1.5 counterparts, indicating the Ni leaching can be decelerated. Graphical Abstract: ga1 Highlights: The PtNi1.5 -(CeO2 )0.8 /C electrocatalyst was prepared by a wet-chemical synthesis strategy with abundant interfaces. The PtNi1.5 -(CeO2 )0.8 /C electrocatalyst presents an excellent mass activity (MA) due to the electronic interaction at the interfaces. The incorporation of suitable CeO2 can increase the diffusion energy barrier of Ni atoms in PtNi1.5 nanoparticles, improving the stability.