首页 > 新闻公告 > CEM研究国际动态 CEM研究国际动态
Anisotropic phase segregation and migration of Pt in nanocrystals en route to nanoframe catalysts

Compositional heterogeneity in shaped, bimetallic nanocrystals offers additional variables to manoeuvre the functionality of the nanocrystal. However, understanding how to manipulate anisotropic elemental distributions in a nanocrystal is a great challenge in reaching higher tiers of nanocatalyst design. Here, we present the evolutionary trajectory of phase segregation in Pt–Ni rhombic dodecahedra. The anisotropic growth of a Pt-rich phase along the left fence111right fence and left fence200right fence directions at the initial growth stage results in Pt segregation to the 14 axes of a rhombic dodecahedron, forming a highly branched, Pt-rich tetradecapod structure embedded in a Ni-rich shell. With longer growth time, the Pt-rich phase selectively migrates outwards through the 14 axes to the 24 edges such that the rhombic dodecahedron becomes a Pt-rich frame enclosing a Ni-rich interior phase. The revealed anisotropic phase segregation and migration mechanism offers a radically different approach to fabrication of nanocatalysts with desired compositional distributions and performance.

Nature Materials (2016) doi:10.1038/nmat4724
Received 22 February 2016 Accepted 04 July 2016 Published online 15 August 2016

http://www.nature.com/nmat/journal/vaop/ncurrent/full/nmat4724.html

发布日期:2016/08/28 发布者: 点击数: