Highly Crystalline Multimetallic Nanoframes with Three-Dimensional Electrocatalytic Surfaces Chen Chen et al. Science 343, 1339 (2014); DOI: 10.1126/science.1249061 This copy is for your personal, non-commercial use only. If you wish to distribute this article to others, you can order high-quality copies for your colleagues, clients, or customers by clicking here. Permission to republish or repurpose articles or portions of articles can be obtained by following the guidelines here. 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Copyright 2014 by the American Association for the Advancement of Science; all rights reserved. The title Science is a registered trademark of AAAS. REPORTS directions. At low T, in the present classical theory magnetic spin fluctuations (16, 17): With decreasing 23. See supplementary materials on Science Online. 24. M. Le Tacon et al., Nat. Phys. 10,52–58 (2014). without randomness, SF vanishes as T → 0; doping, there is a zero-field quantum critical point x 25. L. Nie, G. Tarjus, S. A. Kivelson, http://arxiv.org/abs/1311.5580. however, pinning of the charge order by impurities to the onset of antiferromagnetic order (38), and 26. D. R. Nelson, J. M. Kosterlitz, Phys. Rev. Lett. 39, is likely responsible for the observed SFx (24, 25). this indicates that our present model will have to 1201–1205 (1977). At high T, our assumption of a T-independent bare be extended to explicitly include spin fluctuations 27. L. Li et al., Phys. Rev. B 81, 054510 (2010). 28. I. Kokanović, D. J. 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S.-C. Zhang, Science 275, 1089–1096 (1997). 10.1126/science.1246310 which is found to differ by about 33% from the value obtained from the charge-order correlation length. Considering the simplicity of the N = ∞ theory, the possible differences in the x-ray and Highly Crystalline Multimetallic diamagnetism samples, and the absence of fitting to determine l and w, this result is encouraging. For a sharper comparison, a Monte Carlo study of the Nanoframes with Three-Dimensional crossover into a vortex-dominated regime (30–32) is needed. Eventually, with a complete study that Electrocatalytic Surfaces also includes the effects of disorder and more 1,2,3 4 1,2 1,2 1,2 2 detailed measurements of charge order and super- Chen Chen, * Yijin Kang, * Ziyang Huo, Zhongwei Zhu, Wenyu Huang, Huolin L. Xin, Joshua D. Snyder,4 Dongguo Li,4 Jeffrey A. Herron,5 Manos Mavrikakis,5 Miaofang Chi,6 Karren L. More,6 conducting correlations on the same sample, we 3 4 1,2 1,2,7,8† 4† expect to be able to more tightly constrain the Yadong Li, Nenad M. Markovic, Gabor A. Somorjai, Peidong Yang, Vojislav R. Stamenkovic values of ga2, wa2, l,anda. Control of structure at the atomic level can precisely and effectively tune catalytic properties of Although we have only applied the theory to materials, enabling enhancement in both activity and durability. We synthesized a highly active and a doping where charge order is most pronounced, durable class of electrocatalysts by exploiting the structural evolution of platinum-nickel (Pt-Ni) we argue that it is characteristic of the entire bimetallic nanocrystals. The starting material, crystalline PtNi3 polyhedra, transforms in solution by pseudogap phase. The dominant paradigms for the interior erosion into Pt3Ni nanoframes with surfaces that offer three-dimensional molecular pseudogap have been phase-fluctuating super- accessibility.