Reused spectra are observed in the Figure 4 (a) and (c) of this article [1]. Although the infrared spectra in Figure 4 (a) and (c) are described from different materials, those two spectra look too similar to each other than expect.
Reference
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Parts (in purple boxes) of the lines in Figure 2, the noise patterns look too similar to each other than expected. And the XRD patterns presented in Figure 2 are not consistent to those presented in Figure 4.
