Fan Chenming, Li Guomin, Gu Jingjiu, Wang Qiang, Li Shenggang, Li Bing
School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China.
2020 X-Lab, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, P. R. China.
Small. 2023 Oct;19(40):e2300110. doi: 10.1002/smll.202300110. Epub 2023 Jun 6.
Platinum-rare earth metal (Pt-RE) nanoalloys are regarded as a potential high performance oxygen reduction reaction (ORR) catalyst. However, wet chemical synthesis of the nanoalloys is a crucial challenge because of the extremely high oxygen affinity of RE elements and the significantly different standard reduction potentials between Pt and RE. Here, this paper presents a molten-salt electrochemical synthetic strategy for the compositional-controlled preparation of platinum-neodymium (Pt-Nd) nanoalloy catalysts. Carbon-supported platinum-neodymium (Pt Nd/C) nanoalloys, with distinct compositions of Pt Nd and Pt Nd, are obtained through molten-salt electrochemical deoxidation of platinum and neodymium oxide (Pt-Nd O ) precursors supported on carbon. The Pt Nd/C nanoalloys, especially the Pt Nd/C exhibit a mass activity of 0.40 A mg and a specific activity of 1.41 mA cm at 0.9 V versus RHE, which are 3.1 and 7.1 times higher, respectively, than that of commercial Pt/C catalyst. More significantly, the Pt Nd/C catalyst is remarkably stable after undergoing 20 000 accelerated durability cycles. Furthermore, the density-functional-theory (DFT) calculations confirm that the ORR catalytic performance of Pt Nd/C nanoalloys is enhanced by compressive strain effect of Pt overlayer, causing a suitable weakened binding energies of O and .
铂-稀土金属(Pt-RE)纳米合金被视为一种潜在的高性能氧还原反应(ORR)催化剂。然而,由于稀土元素具有极高的氧亲和力,且铂和稀土之间的标准还原电位存在显著差异,因此通过湿化学方法合成纳米合金是一项严峻的挑战。在此,本文提出了一种熔盐电化学合成策略,用于成分可控地制备铂-钕(Pt-Nd)纳米合金催化剂。通过对负载在碳上的铂和氧化钕(Pt-NdO)前驱体进行熔盐电化学脱氧,获得了具有不同PtNd和PtNd组成的碳载铂-钕(PtNd/C)纳米合金。在相对于可逆氢电极(RHE)为0.9V的电位下,PtNd/C纳米合金,尤其是PtNd/C,表现出0.40A mg的质量活性和1.41mA cm的比活性,分别是商业Pt/C催化剂的3.1倍和7.1倍。更显著的是,PtNd/C催化剂在经历20000次加速耐久性循环后仍具有出色的稳定性。此外,密度泛函理论(DFT)计算证实,PtNd/C纳米合金的ORR催化性能通过Pt覆盖层的压缩应变效应得到增强,从而导致O和的结合能适当减弱。