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Title: Building two-dimensional materials one row at a time: Avoiding the nucleation barrier

Assembly of two-dimensional (2D) molecular arrays on surfaces produces a wide range of architectural motifs exhibiting unique properties, but little attention has been given to the mechanism by which they nucleate. Using peptides selected for their binding affinity to molybdenum disulfide, we investigated nucleation of 2D arrays by molecularly resolved in situ atomic force microscopy and compared our results to molecular dynamics simulations. The arrays assembled one row at a time, and the nuclei were ordered from the earliest stages and formed without a free energy barrier or a critical size. The results verify long-standing but unproven predictions of classical nucleation theory in one dimension while revealing key interactions underlying 2D assembly.

 
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NSF-PAR ID:
10081028
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
American Association for the Advancement of Science (AAAS)
Date Published:
Journal Name:
Science
Volume:
362
Issue:
6419
ISSN:
0036-8075
Page Range / eLocation ID:
p. 1135-1139
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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