Journal
ACS NANO
Volume 6, Issue 11, Pages 10115-10121Publisher
AMER CHEMICAL SOC
DOI: 10.1021/nn3038463
Keywords
hydrogen; quantum tunneling; diffusion; self-assembly; STM; Cu(111)
Categories
Funding
- U.S. Department of Energy [FG02-10ER16170]
- National Science Foundation
- Department of Education for a GAANN Fellowship
- DOE-BES, Office of Chemical Sciences
- U.S. Department of Energy, Office of Science [DE-AC02-06CH11357, DEAC05-00OR22725, DE-AC02-05CH11231]
Ask authors/readers for more resources
Atomic and molecular self-assembly are key phenomena that underpin many important technologies. Typically, thermally enabled diffusion allows a system to sample many areas of configurational space, and ordered assemblies evolve that optimize interactions between species. Herein we describe a system in which the diffusion is quantum tunneling in nature and report the self-assembly of H atoms on a Cu(111) surface into complex arrays based on local clustering followed by larger scale islanding of these clusters. By scanning tunneling microscope tip-induced scrambling of H atom assemblies, we are able to watch the atomic scale details of H atom self-assembly in real time. The ordered arrangements we observe are complex and very different from those formed by H on other metals that occur in much simpler geometries. We contrast the diffusion and assembly of H with D, which has a much slower tunneling rate and is not able to form the large islands observed with H over equivalent time scales. Using density functional theory, we examine the interaction of H atoms on Cu(111) by calculating the differential binding energy as a function of H coverage. At the temperature of the experiments (5 K), H(D) diffusion by quantum tunneling dominates. The quantum-tunneling-enabled H and D diffusion is studied using a semiclassically corrected transition state theory coupled with density functional theory. This system constitutes the first example of quantum-tunneling-enabled self-assembly, while simultaneously demonstrating the complex ordering of H on Cu(111), a catalytically relevant surface.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available