title: Atomic observation of catalysis-induced nanopore coarsening of nanoporous gold.
abstract: Dealloyed nanoporous metals have attracted much attention because of their excellent catalytic activities toward various chemical reactions. Nevertheless, coarsening mechanisms in these catalysts have not been experimentally studied. Here, we report in situ atomic-scale observations of the structural evolution of nanoporous gold during catalytic CO oxidation. The catalysis-induced nanopore coarsening is associated with the rapid diffusion of gold atoms at chemically active surface steps and the surface segregation of residual Ag atoms, both of which are stimulated by the chemical reaction. Our observations provide the first direct evidence that planar defects hinder nanopore coarsening, suggesting a new strategy for developing structurally stable and highly active heterogeneous catalysts.
authors: Advanced Institute for Materials Research, Tohoku University , Sendai 980-8577, Japan.
authors: Takeshi
authors: T
authors: Fujita
authors: Tomoharu
authors: T
authors: Tokunaga
authors: Ling
authors: L
authors: Zhang
authors: Dongwei
authors: D
authors: Li
authors: Luyang
authors: L
authors: Chen
authors: Shigeo
authors: S
authors: Arai
authors: Yuta
authors: Y
authors: Yamamoto
authors: Akihiko
authors: A
authors: Hirata
authors: Nobuo
authors: N
authors: Tanaka
authors: Yi
authors: Y
authors: Ding
authors: Mingwei
authors: M
authors: Chen