Supplemental materials
Fig.S1 (a) shows XRD pattern of as prepared GO. It has a diffraction peak
centered at 2θ = 10.8°, corresponding to a (001) interplanar spacing of 0.81 nm, which
is similar with previous report. 1 The inset of Fig.S1(a) shows the photograph of the
evenly dispersed GO solutions. In the Raman spectrum of GO (Fig.S1b), three sharp
peaks at 1350, 1583 and 2695 cm−1 correspond to the D, G and 2D peaks, respectively.
The intensity ratio of IG/ID is widely used to characterize the defect quantity and a low
ratio indicates a great disorder arising from structural defects.
2
In the absorption
spectrum of as prepared GO (the inset of Fig.S1b), it shows the maximum absorption
peak at 226 nm which was attributed to the π→π* transitions of the C–C bonds. 3 The
absorption shoulder at 260 nm could be attributed to the p→p* transitions of C=C in
as prepared GO. 4
Fig. S1 XRD pattern (a) and Raman spectrum (b) of as prepared GO. The insets are
the corresponding photo of as prepared GO solution and absorption spectrum,
respectively.
Fig.S2 shows Raman spectra of MFCJ ZnO NRs coated with different thickness
of GO sheets under the 633 nm excitation source. At the lower deposition time of GO
(0 and 1 min), no peaks are observed. As the deposition time of GO is increased to 2
min, there occur both peaks at 1327 and 1589 cm−1 corresponding to the D and G
peaks, respectively. By increasing the deposition time of GO from 2 min to 30 min,
both D and G peaks intensity and the intensity ratio of IG/ID decrease, indicated that
the stacking orders of GO decrease. 2, 5
Fig.S2 Raman spectra of MFCJ ZnO NRs coated with different thickness of GO
sheets under the 633 nm excitation source.
Fig.S3 shows absorption spectra of MFCJ ZnO NRs coated with different
thickness of GO sheets. MFCJ ZnO NRs coated with GO sheets show two absorption
bands near 260 and 353 nm. The UV-vis absorption of bulk ZnO has been reported to
appear at 375 nm. 6 The absorption edge of MFCJ ZnO NRs coated with GO sheets
shifted to 353 nm, which is similar with previous report. 7 As above mentioned, the
absorption band at 260 nm (The inset of Fig.S3) could be attributed to the p→p*
transitions of C=C in GO. Comparing MFCJ ZnO NRs coated with different thickness
of GO sheets, the intensity of the carbon related absorption (at 260 nm) increases with
the thickness of GO sheets increases.
Fig.S3 Absorption spectra of MFCJ ZnO NRs coated with different thickness of GO
sheets. The inset shows corresponding enlarged areas marked with grayer ellipse.
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