Surface Engineering of Nanostructured ZnO Surfaces

Zinc Oxide (ZnO) nanostructures represent promising substrate materials for numerous applications, ranging from new generation solar cells, to bio- and chemical sensors. This interest is due to particular physical and chemical properties and highly active surface areas. Despite showing promising perspectives, the performances of ZnO nanomaterials are affected by several drawbacks, including a poor chemical stability against reaction solutions and intrinsic defects that are still preventing their integration into product applications. To overcome some of these limitations, different functionalization strategies have been introduced to engineer the ZnO surface properties. The synthetic methods used for surface functionalization are here discussed and analyzed with respect to the morphology of the agent to be anchored and to the functionalization approach. These approaches range from continuous coatings, to low-dimensional ligands like nanoparticles, photosensible dyes, quantum dots and organic compounds.