A General Solution Synthesis Route to ZnO-Based Nanorod Arrays on Ceramic/Silicon/Quartz Glass/Metal Substrates

We report an effective approach for the growth of vertically aligned one-dimensional (1D) ZnO nanostructures on various substrates (ceramic, silicon, quartz glass and metal) in mild solutions (T = 95 degrees C) without any seeds or catalysts. With the measurements of SEM, FT-IR, XRD and TEM, the novel growth mechanism of the ZnO nanorod arrays has been discussed in detail. The results show that the key of the ZnO direct growth on the demanded substrate is the introduction of glucose into the Zn2+-contained solution, which functionalizes the substrate, leading to the ZnO heterogeneous nucleation on the substrate surface. Particularly noteworthy is that the obtained ZnO is coated with carbonaceous species layer; this layer can be carbonized at high temperature in nitrogen to form core shell composite structures, or removed by oxidation according to different application requirements. Furthermore, it is found that carbon-coated ZnO composite nanostructure shows superior UV excitonic emissions over the pristine ZnO. We believe that our approach presents a general economical route toward mass production of controllable ZnO-based arrays and will facilitate flexible design of device architectures for nanoelectronics.