Surfactant-assisted self-assembly growth of single-crystalline ZnO microflowers at low temperature

Uniform single-crystalline ZnO microflower with well-defined multilayer spiny petals and hexangular prism pistil have been successfully prepared through the surfactant-assisted self-assembly route at 60 °C. For the as-prepared product, three emitting bands were observed, of which included a very strong and broad green light emission at around 580 nm, and two shoulders emission at 404 nm and 439 nm, respectively. ESR experiments confirm that there existed a great fraction of oxygen vacancies in the ZnO microflowers. The possible self-assembly growth mechanism has also been proposed.