Indian researchers (Theivasanthi and Alagar) have controlled shape of lead nanoparticles by using sunbeams. The group, based at Centre for Research and Post Graduate Department of Physics, Ayya Nadar Janaki Ammal College comments: “To our best knowledge, this is the first demonstration for controlling shape of lead nanopowder (Pb) under the influence of sunbeams.
The researchers have explained the detailed procedures in their recent report [Theivasanthi et al, nanobe.org/Pb nanorods ]. http://goo.gl/sIIuK. They have synthesized Pb spherical nanoparticles by electrolysis method using a bioactive compound – konjac (Amorphophallus Paeoniifolius) aqueous extract and such a procedure has so far not been used for nanoparticles preparation. This nanomaterial has potential applications in lead batteries, catalysis, superconductor and photonic crystal. TEM image confirms the 10 nm size of Pb nano-spherical.
In the report: Size and shape provides important control over many of the properties like physical, chemical and catalytic properties of nanomaterials. When nanomaterials interact with biological systems, their properties are changed significantly, may also be desirable characters in sometimes. While, on contact with a biological fluid they may become coated with proteins and other bio-molecules. Capping agents assisted synthesis methods usually produce spherical particles due to the low surface energy associated with such particles.
The researchers have said that generally, metal nanoparticles strongly absorb light in the visible region due to Surface Plasmon Resonance (SPR) and the absorbed light promotes some reactions on the nanoparticles. “On this basis, an attempt has been made to explore the effects of the sunlight on Pb nanoparticles and to find the possibilities for dual function utilization of sunlight i.e. as a dryer for the synthesized nanomaterials and as a morphological changer. The result explicates that it is possible to change the shape of Pb nanoparticles (konjac extract added) from spherical to rod by the influence of sunbeams”, the researchers comment, adding: “Further research work is under process to find the possibility of morphological effect changes by sunlight, in other metal nanoparticles with konjac extract or other bio-molecules”.