The peak position of the visible light emission band is similar to those of previous studies of nanostructured ZGO phosphors [23]. The visible light emission band for ZGO originates from its native defects [24]. The formation of the ternary ZGO compound through a high-temperature solid-state reaction might involve the formation of native defects, such as oxygen vacancies, in the ZGO crystals [18]. This is supported by our XPS O 1 s analysis, which indicated oxygen vacancies

in the ZGO lattice. NVP-BSK805 molecular weight The solid-state reaction induced crystal defects in ZnO-ZGO, which might account for the difference in the PL spectra between ZnO-Ge and ZnO-ZGO. Figure 3 PL spectra of the ZnO-Ge (black line) and ZnO-ZGO (red line) heterostructures. Figure 4a presents a TEM image of the morphology of a single 1D ZnO-ZGO heterostructure, showing that the surface of ZnO-ZGO was rugged. Figure 4b shows the electron diffraction pattern of the ZnO-ZGO structure. Tiny spots formed clear ringlike patterns associated with polycrystalline ZGO crystals. Moreover, sharp, bright, large spots appeared to emanate from the ZnO layer of the ZnO-ZGO structure. Figure 4c,d,e shows high-resolution images of various regions of the ZnO-ZGO structure. In Figure 4c,d, small surface groves are present on the structure. Clear, ordered lattice fringes present on the outer layer of the structure are assigned to the ZGO crystalline phase according to the

fast Fourier transform pattern (insets in Figure 4c,d). The interplanar d-spacing evaluated based on the lattice fringes TCL was approximately 0.71 nm, which corresponds to the 110 lattice planes of the well-crystalline ZGO Vorinostat price structure. The corresponding 0.41 nm is ascribed to the 300 lattice planes. Moreover, Figure 4e shows that the arrangement of lattice fringes of the ZGO layer is relatively more random than that in Figure 4c,d. The multiple 110-, 300-, and 520-oriented lattice fringes are presented in Figure 4e. The HRTEM image analysis results indicated that some ZGO crystallites

formed a favorable crystallographic match with the ZnO crystal, whereas others showed multi-oriented features. According to the TEM observation, the thickness of the ZGO crystallites ranged from approximately 17 to 26 nm. Figure 4 Low- and high-magnification TEM images and electron diffraction pattern of the ZnO-ZGO heterostructure. (a) Low-magnification TEM image of a single ZnO-ZGO heterostructure. (b) Electron diffraction pattern of the heterostructure. (c, d, e) High-resolution images of the heterostructure taken from various regions. The corresponding FFT images taken from the local lattice fringes are also shown in the insets. Figure 5 shows the dynamic UV light photoresponse curve of ZnO-ZGO measured in ambient air at room temperature. ZnO-ZGO shows UV light photocurrent sensitivity. The increase and decrease of photocurrents show a time-dependent function in the presence and absence of UV lights, respectively.