Authors: C. Verissimo, A. Abbaspourrad, K. Sunter, F. Capasso, S. Moshkalev, D. Weitz
Affilation: University of Campinas - UNICAMP, Brazil
Pages: 281 - 283
Keywords: hierarchical structures, ZnO, synthesis
Hierarchical oxide nanostructures are very promising materials for different applications, such as gas sensing, due to their high surface area. Literature shows that hierarchical nanostructures improve gas sensing response and response speed. This effect is due to the effective gas diffusion toward the sensing surfaces. Gas sensing properties of ZnO materials have been investigated and the influence of the 3D structure has been evaluated. Yangang Sun et al. showed a response improvement in the gas sensing for ZnO flower-like microstructures. This behavior has being attributed to more active centers that are obtained from the enhanced oxygen vacancy defects on the junctions within the ZnO flower-like 3D structures. In this work, we present a hydrothermal procedure to synthesize ZnO with flower-like morphology. Controlling experimental parameters it is possible to obtain branched structures, which results in the preparation of materials presenting even higher surface area. Different reaction mediums have being tested, such as water, water/glycerol, and deuterium solutions. Moreover, several polymers have being investigated as shape driving molecules. Rare earth metals have also being introduced in the ZnO structure and the influence in the final morphology has being evaluated.