These are images of Zinc Oxide crystals. The nanoflowers are a biproduct of a reaction which grows zinc oxide nanowires on a piece of zinc metal. Zinc Oxide nanoflowers are one of the many kinds of Zinc Oxide nanostructures that can be synthesized.

These nanostructures are piezoelectric, which means that they develop a charge when mechanically deformed. Due to this, these structures are of interest for a variety of applications ranging from sensing apparatuses for enzymatic activity and photoluminescent sensors to nanoscale energy generation from harvested mechanical motion. Understanding the properties and behaviors of these structures is a key step towards the miniaturized and implantable biosensor platforms of tomorrow.