Mun D-H, Bak S J, Ha J-S, Lee H-J, Lee J K, Lee S H, Moon Y B
J Nanosci Nanotechnol. 2014 Aug;14(8):5970-5. doi: 10.1166/jnn.2014.8308.
In this study, we grew ZnO nanowires hydrothermally on (1-102) r-plane sapphire substrates in an aqueous solution which contained zinc nitrate hexahydrate and hexamethylenetetramine (HMT) at 90 °C. First, the AZO seed layer of 80 nm thickness was deposited on the r-plane sapphire substrate by a radio frequency magnetron sputter. After that, we grew the ZnO nanowires on the seed layer by changing the precursor concentration of the aqueous solution from 0.025 M to 0.01 M. When the molar concentration of the precursor was changed, the diameter, length, density and number of ZnO nanowires also changed significantly: diameter, length and density increased with increasing molar concentration but the number of ZnO nanowires decreased. The ZnO nanowires grown at the higher molar concentration tended to grow along with the c-axis direction, as revealed by atomic force microscope and X-ray diffraction peaks. Furthermore, the PL spectra measured at room-temperature revealed a UV emission of 380 nm which can be attributed to the radiative recombination of free and bound excitons (Near Band edge Emission). The NBE emission was also increased with increasing molar concentration.
在本研究中，我们于90℃下，在含有六水合硝酸锌和六亚甲基四胺（HMT）的水溶液中，通过水热法在（1-102）r面蓝宝石衬底上生长氧化锌纳米线。首先，通过射频磁控溅射在r面蓝宝石衬底上沉积80nm厚的AZO籽晶层。之后，我们通过将水溶液的前驱体浓度从0.025M改变为0.01M，在籽晶层上生长氧化锌纳米线。当前驱体的摩尔浓度改变时，氧化锌纳米线的直径、长度、密度和数量也发生了显著变化：直径、长度和密度随着摩尔浓度的增加而增加，但氧化锌纳米线的数量减少。如原子力显微镜和X射线衍射峰所示，在较高摩尔浓度下生长的氧化锌纳米线倾向于沿c轴方向生长。此外，室温下测量的PL光谱显示出380nm的紫外发射，这可归因于自由激子和束缚激子的辐射复合（近带边发射）。近带边发射也随着摩尔浓度的增加而增加。
