Microwave heating has been used before by scientists to synthesize micron-sized ZnO particles, but Husnu Emrah Unalan and his colleagues have taken the method a step further by growing ZnO nanowires on a range of substrates including silicon, glass and PET. The large-area technique is expected to open up applications ranging from LEDs to antireflective coatings.

"Large area synthesis is possible with other methods, such as chemical vapour deposition, but this requires a much higher level of technical complexity," Unalan told nanotechweb.org. "Our system is very straightforward."

To grow their ZnO nanowires, the researchers place a seeded substrate in an aqueous solution of zinc nitrate hexahydrate and hexamethylenetetramine and then heat the set-up in a domestic microwave for 1–30 minutes.

As well as being quick to produce, the microwave-grown nanowires appear to have fewer defects compared with furnace grown material, which could benefit future devices.

The researchers presented their work in Nanotechnology.