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Title: A technique for efficiently generating bimetallic clusters

Abstract

Reactivities of bimetallic clusters can be controlled by varying their composition, making them potentially valuable as catalysts and for use in elucidating the reactivities of such subnanoscale surfaces. A dual rod laser vaporization source coupled to a fast flow reactor is developed for the study of bimetallic clusters and their reactions. In order to establish the versatility of the technique, the results of studies are presented in which Nb/Al clusters are formed in two plasmas induced by the second harmonic (532 nm photons) of a single Nd:YAG laser and then detected by a quadrupole mass spectrometer. The beam from the laser is split and then focused onto each rod, allowing the mixing ratio within the cluster to vary by altering the laser fluence on each rod. With a low fluence on the Nb rod and a high fluence on the Al rod, an Al rich cluster distribution is formed, NbAl{sub m}{sup {minus}} (m=2{endash}20), and Al{sub m}{sup {minus}} (m=5{endash}31). By increasing the fluence on the Nb rod and decreasing the fluence on the Al rod, a Nb rich cluster distribution is formed, Nb{sub n}Al{sub m}{sup {minus}} (n=3{endash}8 and m=1{endash}3), Nb{sub n}OAl{sub m}{sup {minus}} (n=3{endash}8 and m=1{endash}5), and Nb{sub n}O{sup {minus}} (n=3{endash}8).more » Additional characterization is also performed on V/Al clusters. {copyright} {ital 1997 American Institute of Physics.}« less

Authors:
; ;  [1]
  1. Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
Publication Date:
OSTI Identifier:
548834
DOE Contract Number:
FG02-92ER14258
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 68; Journal Issue: 8; Other Information: PBD: Aug 1997
Country of Publication:
United States
Language:
English
Subject:
66 PHYSICS; ATOMIC CLUSTERS; FABRICATION; SOLID CLUSTERS; SYNTHESIS; ALUMINIUM; NIOBIUM; LASER-PRODUCED PLASMA; LASER RADIATION; CATALYSTS

Citation Formats

Wagner, R.L., Vann, W.D., and Castleman, A.W. , Jr. A technique for efficiently generating bimetallic clusters. United States: N. p., 1997. Web. doi:10.1063/1.1148058.
Wagner, R.L., Vann, W.D., & Castleman, A.W. , Jr. A technique for efficiently generating bimetallic clusters. United States. doi:10.1063/1.1148058.
Wagner, R.L., Vann, W.D., and Castleman, A.W. , Jr. 1997. "A technique for efficiently generating bimetallic clusters". United States. doi:10.1063/1.1148058.
@article{osti_548834,
title = {A technique for efficiently generating bimetallic clusters},
author = {Wagner, R.L. and Vann, W.D. and Castleman, A.W. , Jr.},
abstractNote = {Reactivities of bimetallic clusters can be controlled by varying their composition, making them potentially valuable as catalysts and for use in elucidating the reactivities of such subnanoscale surfaces. A dual rod laser vaporization source coupled to a fast flow reactor is developed for the study of bimetallic clusters and their reactions. In order to establish the versatility of the technique, the results of studies are presented in which Nb/Al clusters are formed in two plasmas induced by the second harmonic (532 nm photons) of a single Nd:YAG laser and then detected by a quadrupole mass spectrometer. The beam from the laser is split and then focused onto each rod, allowing the mixing ratio within the cluster to vary by altering the laser fluence on each rod. With a low fluence on the Nb rod and a high fluence on the Al rod, an Al rich cluster distribution is formed, NbAl{sub m}{sup {minus}} (m=2{endash}20), and Al{sub m}{sup {minus}} (m=5{endash}31). By increasing the fluence on the Nb rod and decreasing the fluence on the Al rod, a Nb rich cluster distribution is formed, Nb{sub n}Al{sub m}{sup {minus}} (n=3{endash}8 and m=1{endash}3), Nb{sub n}OAl{sub m}{sup {minus}} (n=3{endash}8 and m=1{endash}5), and Nb{sub n}O{sup {minus}} (n=3{endash}8). Additional characterization is also performed on V/Al clusters. {copyright} {ital 1997 American Institute of Physics.}},
doi = {10.1063/1.1148058},
journal = {Review of Scientific Instruments},
number = 8,
volume = 68,
place = {United States},
year = 1997,
month = 8
}
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