A non-catalytic and template-free method has been developed to form quasi-aligned zinc-sulfur (ZnS) nanobelts, by scientists in Japan.

It is known that ZnS has a wide bandgap and thus is a very good semiconductor, and is subsequently an important material in the electronics industry. Usually ZnS nanostructures are synthesized by randomly placing them on to the substrates. 

Xiaosheng Fang and co-workers from the National Institute for Materials Science in Ibaraki, have reported ZnS nanobelts with a different structure and shape from those previously reported. These nanobelts were aligned on a micro/macroscopic scale and also displayed similar crystallographic orientation to their growth axes. 

Furthermore, field-emission (FE) measurements were carried out on these nanobelts and the observed field emission properties surpassed that of some already pre-existing FE materials.

'The measured emission current densities reached ~14.6 mA/cm² at a macroscopic field of 5.5 V/mm, which is more than 20 times of that in randomly oriented ZnS nanobelts' said Fang.

This new method shows that growing a large area of orientation-ordered ZnS nanobelts, which grow uniformly and aligned, enhances their field-emitting ability. In the future, this material could be utilised in novel field emitters, luminescence and electronic devices, as well as in the development of sensors.

Emma Shiells