Shape-controlled synthesis of zinc oxide by microwave heating using an imidazolium salt

Zinc oxide (ZnO) with flowerlike and needlelike shapes has been successfully synthesized by a simple microwave-assisted solution phase approach using an imidazolium salt 1-n-butyl-3-methyl imidazolium tetrafluoroborate ([BMIM]BF4) (an ionic liquid). By controlling experimental conditions, exclusive ZnO needles or flowers could be synthesized in a short period of time (5 or 10 min).