Self-assembled ZnO-rGO nanocomposite, a solid-state transformation to control its crystallite size

Reduction of graphene oxide (GO) to reduced graphene oxide (rGO) at different hydrothermal temperatures and enhanced photodegradation of zinc oxide/rGO composites

“…The Raman peak at 437 cm −1 was associated with a high E 2 , and that at 1123 cm −1 was due to second-order modes [12,16,31,38]. The Raman peak at 329 cm −1 was due to the 3E 2H -E 2L phonon modes of the ZnO structure [12,31]. The Raman peak at 437 cm −1 was due to the E 2 (high) phonon mode of the wurtzite structure of ZnO [12,16,31,38].…”

“…In this study, we used the Scherrer formula from equation (1) [29][30][31][32] to calculate the average crystal size of ZnO from the ZnO/rGO nanopatterns, where λ refers to the x-ray wavelength, θ indicates the Bragg diffraction angle, and β is the FWHM. Table 1 shows the crystal size of ZnO in the ZnO/rGO nanopatterns calculated using the Scherrer formula.…”

“…A more detailed study of the Raman peaks associated with ZnO crystals indicated that the Raman peak at 329 cm −1 was related to the coupling of multiple phonons in the E 2 modes of Zn and O sublattice vibrations (low E 2 ) [12,16,31,38]. The Raman peak at 437 cm −1 was associated with a high E 2 , and that at 1123 cm −1 was due to second-order modes [12,16,31,38]. The Raman peak at 329 cm −1 was due to the 3E 2H -E 2L phonon modes of the ZnO structure [12,31].…”

“…The Raman peak at 329 cm −1 was due to the 3E 2H -E 2L phonon modes of the ZnO structure [12,31]. The Raman peak at 437 cm −1 was due to the E 2 (high) phonon mode of the wurtzite structure of ZnO [12,16,31,38]. In addition, the broad Raman peak at 1123 cm −1 contained contributions of the phonon modes of 2A 1 (LO) and 2E 1 (LO) in the Brillouin zone of ZnO [16,31,38].…”

“…The Raman peak at 437 cm −1 was due to the E 2 (high) phonon mode of the wurtzite structure of ZnO [12,16,31,38]. In addition, the broad Raman peak at 1123 cm −1 contained contributions of the phonon modes of 2A 1 (LO) and 2E 1 (LO) in the Brillouin zone of ZnO [16,31,38]. From the results shown in table 3, the position, FWHM, and intensity of ZnO peaks hardly changed as the hydrothermal temperature was increased.…”