B. Das et al. / Chemical Physics Letters 477 (2009) 160–163
163
Table 2
Selected Raman band positions (cmꢀ1) and enhancement factors (EF) of pyridine on nanocrystalline Au films.
Liquid peak positions (relative
intensity)
t
Films of 12 nm Aua
Films of 15 nm Aua
Films of 13 nm Aub
Peak positions (relative
intensity)
EF
Peak positions (relative
intensity)
EF
Peak positions (relative
intensity)
EF
992, A1 (100)
1032, A1 (82)
1068, A1 (2)
1
12
1000 (100)
1029 (42)
2.3 ꢁ 104 1001 (100)
1.2 ꢁ 104 1030 (41)
5.0 ꢁ 105 1096 (33)
4.0 ꢁ 104 999 (100)
2.0 ꢁ 104 1033 (98)
6.0 ꢁ 105 1097 (11.5)
3.3 ꢁ 103
3.1 ꢁ 103
2.9 ꢁ 104
18a 1097 (43)
t
= Wilson number; EF = enhancement factor.
a
By THPC route.
b
By hydrazine hydrate route.
used as substrates for SERS studies of molecules. The intensity
enhancement and band shifts of pyridine found on these thin films
are comparable to those reported for other Au and Ag substrates.
The ease with which nanocrystalline metal films are prepared at
the interface favor their use for SERS studies.
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4. Conclusions
The results of the present study show that nanocrystalline films
of Au and Ag generated at the organic–aqueous interface can be