Nanoscopic Naked Cu/Pd Powder
J. Phys. Chem., Vol. 100, No. 50, 1996 19537
08246101) from Ministry of Education, Science, Sport and
Culture, Japan. Y.W. thanks Japan Society for the Promotion
of Sciences for the grant of a JSPS fellowship.
References and Notes
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Figure 7. Time courses of hydrogenation of 1,3-cyclooctadiene
catalyzed by the ultrafine powder catalysts: Cu/Pd (1/1) ([), Cu/Pd
(2/1) (O), Cu/Pd (3/1) (b), and Pd (0). Reaction conditions were as
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ethanol; Pd content, 0.131 mmol; COD, 0.58 mmol.
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is different from the usual reduction and aggregation process
for the preparation of metal particles from metal ions in solution
but is characterized by formation of bimetallic hydroxide colloid
before the reduction process. The bimetallic powder has been
characterized by XRD, IR, AAS, XPS, and its catalytic
properties. Both Cu and Pd are reduced to a valence state of
zero in the present process and the structure of the bimetallic
Cu/Pd powder is Cu/Pd alloy or solid solution. Catalytic
properties of the bimetallic powder for selective hydration of
acrylonitrile to acrylamide and for selective partial hydrogena-
tion of 1,3-cyclooctadiene to cyclooctaene have been studied.
In the hydration reaction, the bimetallic powder catalyst exhibits
good stability against air and high activity as well as high
selectivity for the formation of acrylamide. In the hydrogenation
reaction, both the activity and selectivity are strongly dependent
on the Cu/Pd ratio.
Acknowledgment. The authors express their sincere thanks
to Drs. S. Fukuda and K. Adachi of the University of Tokyo
for the assistance in taking electron micrographs. This work is
supported by a Grant-in-Aid for Scientific Research (B) (No.
054531541) and Grant-in-Aid for Scientific Research on Priority
Areas “New Polymers and Their Nano-Organized Systems” (No.
JP961877G