10.1021/jacs.7b05584.s002 Nigel Becknell Nigel Becknell Yoonkook Son Yoonkook Son Dohyung Kim Dohyung Kim Dongguo Li Dongguo Li Yi Yu Yi Yu Zhiqiang Niu Zhiqiang Niu Teng Lei Teng Lei Brian T. Sneed Brian T. Sneed Karren L. More Karren L. More Nenad M. Markovic Nenad M. Markovic Vojislav R. Stamenkovic Vojislav R. Stamenkovic Peidong Yang Peidong Yang Control of Architecture in Rhombic Dodecahedral Pt–Ni Nanoframe Electrocatalysts American Chemical Society 2017 oxygen reduction reaction Pt alloy electrocatalysts proton exchange membrane fuel cells mass activity nanoframe 2017-08-08 00:00:00 Media https://acs.figshare.com/articles/media/Control_of_Architecture_in_Rhombic_Dodecahedral_Pt_Ni_Nanoframe_Electrocatalysts/5313616 Platinum-based alloys are known to demonstrate advanced properties in electrochemical reactions that are relevant for proton exchange membrane fuel cells and electrolyzers. Further development of Pt alloy electrocatalysts relies on the design of architectures with highly active surfaces and optimized utilization of the expensive element, Pt. Here, we show that the three-dimensional Pt anisotropy of Pt–Ni rhombic dodecahedra can be tuned by controlling the ratio between Pt and Ni precursors such that either a completely hollow nanoframe or a new architecture, the excavated nanoframe, can be obtained. The excavated nanoframe showed ∼10 times higher specific and ∼6 times higher mass activity for the oxygen reduction reaction than Pt/C, and twice the mass activity of the hollow nanoframe. The high activity is attributed to enhanced Ni content in the near-surface region and the extended two-dimensional sheet structure within the nanoframe that minimizes the number of buried Pt sites.