Individual and collective electronic properties of Ag nanocrystals

Journal Article · Thu Nov 25 04:00:00 EST 1999 · Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical

DOI:https://doi.org/10.1021/jp991952y· OSTI ID:20013638

Kim, S H; Medeiros-Ribeiro, G; Ohlberg, D A.A.; Williams, R S; Heath, J R

The authors report on the electronic transport properties of individual alkanethiol-passivated Ag nanocrystals and their superlattices. Isolated Ag particles with diameters in the range of 2.7--4.8 nm supported by a metallic substrate passivated with an organic layer show a Coulomb gap. Monolayer films of Ag particles exhibit four distinct electronic signatures, two of which have not been previously reported, depending on their structures. In two-dimensional ordered superlattices of octanethiol-capped 4.8 nm diameter nanocrystals on graphite, the strong interparticle electronic coupling produces metallic films. A disordered monolayer of dodecanethiol-capped 6.6 nm diameter nanocrystals exhibits a temperature-dependent differential conductance, which is attributed to the localized states formed by the disorder in the lattice. For two-dimensional ordered superlattices of pentanethiol- and hexanethiol-capped 2.7 nm diameter Ag particles. It was shown that the films are insulating, and individual nanocrystals maintain their individual electronic identity. Two different types of insulating films have been observed: one with electronically homogeneous nanocrystals in a close-packed lattice and the other with sublattices of electronically distinct monocrystals within a square lattice. The relationship of the Coulomb blockade and nanocrystal ordering to the electronic behavior of this class of architectonic materials are discussed.

• Research Organization: Hewlett-Packard Labs., Palo Alto, CA (US)
• OSTI ID: 20013638
• Journal Information: Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical, Journal Name: Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical Journal Issue: 47 Vol. 103; ISSN 1089-5647; ISSN JPCBFK
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ELECTRICAL PROPERTIES
ELECTRONIC STRUCTURE
FILMS
OPTICAL PROPERTIES
PARTICLES
PASSIVATION
SILVER
THIOLS