Nanotechnologists treading on eggshells

Nanotechnologists in China have found the perfect way to synthesise a compound vital to the development of optoelectronics – and to do it they have turned to eggshells.

An eggcellent breakthrough for some eggstatic nanotechnologists (sorry, too good to miss. Ed)

Lead sulphide (PbS) - a semiconductor widely used in photovoltaic conversion devices, optical switches and other photoelectric applications – has unique optical, electronic and photovoltaic properties that depend on the shape, structure and distribution of the nanoparticles. So far scientists have struggled to construct well-organised PbS nanoparticles under ambient conditions.

Huilan Su from Shanghai Jiao tong University and colleagues may now have come up with a solution to this – by using eggshell membranes as the reactive substrates for the formation and assembly of PbS nanocrystallites.

Eggshell membranes are collagen-based matrices found between the egg white and the mineralised shell of an egg and proved a good base upon which the team could grow the nanocrystals. After the procedure, the team saw that the PbS nanoclusters were arranged in a very orderly way on the membrane fibres.

Su said: “The PbS nanoclusters not only have good quantum size effects and are well distributed, but they also exhibit excellent biocompatibility. When combined with the reactive biosubstrate, the nanocomposites could be promising for applications in photoelectronics, photonics and electronics.”
The researchers think that this simple, inexpensive fabrication technique could easily lend itself to industrial scale. They will now investigate other biomaterials, such as silk fibre, butterfly wings and bird's feathers, as the biosubstrates and templates for functional nanostructures.

The work was reported in Smart Materials and Structures.