A.K. Patra et al. / Catalysis Communications 11 (2010) 651–655
655
late was reduced to aminophenolate. In absence of any catalyst,
NaBH4 reduce the 4-nitrophnolate moiety to a very small extent
(shown in Fig. 4C). On the other hand commercial Cu nanopowder
(Sigma–Aldrich, particle size <100 nm) catalyzes this reduction to
47.2 mol% in 1 h reaction time. Hence copper nanoparticles synthe-
sized herein, acting as efficient catalysts for reduction to occur.
From the UV–vis plots in Fig. 4A and B it is further revealed that
for the Cu nanospheres (spherical particles of size 2–15 nm) within
1 h reaction reaches maximum conversion level (ca. 94%), whereas
for Cu nanorods (14 nm  100–235 nm) it reaches much lower
conversion level (ca. 76%) even after 1.5 h reaction time. This result
suggests that Cu nanosphere is more efficient catalyst than Cu
nanorod in this reduction reaction. Smaller size of the particles to-
one pot at room temperature, suggesting the role of particle size
and shape in catalytic reduction.
Acknowledgement
AKP and AD thank CSIR, New Delhi for junior research
fellowships.
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