Template Synthesis of Nanostructured Metals Using Cellulose Nanocrystal - The Nanoscience and Technology of Renewable Biomaterials - page 331

1.00E + 00

1

8.00E 01

−

0.8

6.00E − 01

0.6

4.00E − 01

0.4

2.00E − 01

0.2

0.00E + 00 0

400 500 600 700 800 0 20 40 60 80 100

Wavelength (nm) Reaction time (min)

(a) (b)

Figure12.13 (a)UV-Visspectrafor thephotodegradationofMBinwater:Thetimeinterval
betweensuccessivemeasurementsis10min.[MB] 10 −5 M.

(b) Absorbance as a function of reaction time in the presence of Se nanoparticles: (

10 −5 Mand[Se]

= 5.0 × = 1.0 ×

)no

catalyst,( )commercialSecatalyst,and( )SenanoparticlesonCNXL.

However, high temperature thermal treatment under N 2 is required for metal ions such
as Cu(II) and Ni(II) because of their high oxidizing property. CNXL is an ideal tem-
plate for homogeneous distribution of metal ions on its surface due to the presence
of hydroxyl groups, which immobilize metal ions. Detailed reduction pathways of
metal ions are still a puzzle, even though surface-initiated reaction is clear. The fun-
damental investigation for the reduction mechanism is under study. The homogeneous
dispersion of monodisperse metal nanoparticles on CNXL through the 'green' reducing
process can be expected to have a huge impact in the application of clean heterogeneous
catalysis.

Acknowledgements

Authors would like to thank Dr C. Wang, Dr I.-T. Bae, and Mr B.W. Arey for their
microscopic measurements. Pacific Northwest National Laboratory is operated by Bat-
telle for the US Department of Energy under Contract DE-AC06-76RL0 1830. This work
is supported by the Office of Basic Energy Sciences, Materials Sciences and Engineering
Division, of US Department of Energy.

References

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Chem. Rev . 1993, 93, 267-300.

3. Lippard, S.J.; Berg, J.M., Principles of Bioinorganic Chemistry , University Science

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