The chemical composition and crystalline property of the
HSNs were investigated using EDS elemental analysis and
powder XRD patterns. The hollow nanomaterials with different
shapes showed similar chemical composition and crystalline
property. Here the results for the HSiNWs were presented as
an example. The EDS spectrum in Figure 2A was obtained
from a single nanowire of the indicated yellow area on the SEM
image (Figure 2A, inset). EDS analysis demonstrated that the
nanowire contained Si and O with an approximate atomic ratio
of Si:O = 1:2. Apart from Si and O signals, peaks of Al and Na
were also detected, which was from the SEM sample supporter
(made of Al) and residue of the synthesis (the addition of
Na3Ct in the synthesis of silica nanowire). The XRD pattern of
the synthesized HSiNWs is shown in Figure 2B. The scattering
pattern exhibited one broad peak ranging from 15 to 30° with
the peak value at a 2θ angle of 24°, indicating the amorphous
nature of the HSiNWs. It was reported that one-dimensional
amorphous HSiNWs are good candidates for photoluminescent
materials because of their unique blue-light emission.26−30
Therefore, the amorphous characteristic of the prepared
HSiNWs may have potential applications in nanoelectronic
devices