作者机构：[Fujita, T] Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan, PRESTO, JST, 4-1-8 Honcho, Kawaguchi, Saitama 332-00 更多[Fujita, T] Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan, PRESTO, JST, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan;[ Tokunaga, T] Ecotopia Science Institute, Nagoya University, Nagoya 464-8603, Japan;[ Zhang, L] Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan;[ Li, D] Center for Advanced Energy Materials and Technology Research (AEMT), School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China;[ Chen, L] Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan;[ Arai, S] Ecotopia Science Institute, Nagoya University, Nagoya 464-8603, Japan;[ Yamamoto, Y] Ecotopia Science Institute, Nagoya University, Nagoya 464-8603, Japan;[ Hirata, A] Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan;[ Tanaka, N] Ecotopia Science Institute, Nagoya University, Nagoya 464-8603, Japan;[ Ding, Y] Center for Advanced Energy Materials and Technology Research (AEMT), School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China;[ Chen, M] Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan, State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030, China, CREST, JST, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan 收起
关键词：CO oxidation;heterogeneous catalyst;environmental transmission electron microscopy;nanoporous metal;In situ TEM
摘要：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.
