Fabrication and characterization of In-doped zinc oxide nanodisks

In-doped ZnO nanodisks were successfully fabricated by thermal evaporation Zn, In2O3, and graphite powder mixture without catalyst. SEM images show that some ZnO nanodisks have perfect hexagonal shape, and others have dodecagon shape. These nanodisks are about 1 similar to 3 mu m in size and 40-100 nm in thickness. XRD, TEM, and EDS investigations confirm single-crystalline ZnO with wurtzite structure. The hexagonal nanodisks grow mainly along the six symmetric directions of < 10 (1$) over bar0 >, and the dodecagonal nanodisks grow along < 2 (1) over bar(1) over bar0 > and < 10 (1) over bar0 >, with both kinds of nanodisks' growth along [00011 being suppressed. The In content of nanodisks reaches 2.2%. A possible mechanism is also proposed. Room temperature photoluminescence spectra of the nanodisks shows that the UV emission peak blueshifts and becomes broader after doping. These materials as building blocks have potential in applications such as optoelectronics.