Collective Osmotic Shock- A New Method To Create Nanoporous Materials

The conventional method of creating nanoporous materials involves removing minor quantities of material and leaving voids in its place. One disadvantage in this method is the void must continuous throughout the material and must form a network for the proper removal of the materials from inside also. This has kept the production of nanoporous material limited till now. When produced effectively it will have potential applications from water purification to optical communications.

The new research by the Cambridge university scientists, published in the <em>Nature Materials</em> journal (27 November issue) speaks of a new method called Collective Osmotic Shock to produce the nanoporous materials more effectively. The osmotic forces will aid in forming a nanoporous material by deforming the matrix formation and creating the voids in between.

Dr. Easan Sivaniah, the lead author #-Link-Snipped-#, ‘We broke down the polymers on the inside into small molecules using a bit of heat, sunshine and some vinegar. The molecules have a high solubility, so if you introduce a solvent it will dissolve as many of them as possible and this induces a large osmotic pressure.’ He also #-Link-Snipped-#, “In our experiments, we essentially show this works in materials with these trapped minor components, leading to a series of bursts that connect together and to the outside, releasing the trapped components and leaving an open porous material.”

The application of this material has large scope. The primary use of this material could be for filtration. ‘It is currently an efficient filter system that could be used in countries with poor access to fresh potable water, or to remove heavy metals and industrial waste products from ground water sources’ says Dr. Easan Sivaniah. The filtration at nanoscale could enable filtration of color dyes. The other such application is the desalination of sea water. Layers of materials separated by other materials of different densities can be used as diffraction gratings or as wave guides in optical communications. Using the nanoporous materials this varying density can be easily achieved.

Dr Sivaniah added, “We are currently exploring a number of applications, to include use in light-emitting devices, solar cells, electrodes for super capacitors as well as fuels cells.”