3 years ago

Composition-Graded PdxNi1–x Nanospheres with Pt Monolayer Shells as High-Performance Electrocatalysts for Oxygen Reduction Reaction

Composition-Graded PdxNi1–x Nanospheres with Pt Monolayer Shells as High-Performance Electrocatalysts for Oxygen Reduction Reaction
Shuiyun Shen, Renxiu Tian, Liuxuan Luo, Junliang Zhang, Xiaohui Yan, Lin Li, Fengjuan Zhu
It is undoubtedly desirable, albeit very challenging, to appropriately balance the catalytic activity, electrochemical durability, and noble-metal (NM) utilization when developing Pt-based catalysts for oxygen reduction reaction (ORR). Accordingly, in this work, a versatile and effective strategy that promises the nanostructure of both composition-graded core and mono- or multilayer shell is proposed to synthesize highly uniform, sub-10 nm PdxNi1–x@Pt nanospheres (NSs) as high-performance ORR electrocatalysts. Highly uniform and composition-graded PdxNi1–x NSs are previously obtained via a facile one-pot Ni-substitution-based process, and then Pt mono- or multilayer shells are coated onto them through Cu underpotential deposition coupled with Pt2+ galvanic displacement. Results show that carbon-supported PdxNi1–x@Pt electrocatalysts possess both high catalytic activity and highly efficient NM utilization toward ORR. The optimized Pd0.42Ni0.58@Pt/C exhibits 0.61 mA cm–2, 0.42 A mg–1Pd+Pt, and 1.45 A mg–1Pt @ 0.9 V (vs RHE) in the area-specific, NM-mass-specific, and Pt-mass-specific activity, respectively, reaching 2.8, 3.3, and 11.2 times relative to those of the commercial Pt/C. Moreover, Pd0.42Ni0.58@Pt/C also has a satisfactory electrochemical durability, preserving its high ORR catalytic activity even after 12 000 potential cycles of the accelerated degradation test. The synthetic mechanism of PdxNi1–x NS core, Pt monolayer shell and their combined effects on the catalytic activity, electrochemical durability, and NM utilization of PdxNi1–x@Pt/C toward ORR are comprehensively investigated.

Publisher URL: http://dx.doi.org/10.1021/acscatal.7b01775

DOI: 10.1021/acscatal.7b01775

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.