Research

Nanostructures & Characterization   |   Cumputational Modeling  |   Micro/Nano Biosensors   |   Bioengineering   

In this area the group specializes in preparation of micro and nano scale structures and textured substrates using physical, electrochemical, and microfabrication methods.

Currently we have developed nano rods using electrochemical techniques. We prepared porous alumina templates by oxidising aluminium. We elecrodeposited the required metal and dissolved alumina to obtain the nanorods. By this technique we have prepared Au,Ag and NiO nanorods.We use these nanorods for increasing the sensitivity of BioSensors.

The following are details of the specific research done:

Preparation of porous anodized Alumina

Anodization is an electrochemical process in which the metals such as aluminum, titanium are oxidized. Anodization of aluminum leads to a regularly ordered nanosized pores on its surface which can be used as template in growing nanowires. We have created the porous anodized alumina structure on a titanium coated silicon substrate. The nanostructures can be directly grown into the pores of alumina on Titanium coated silicon substrate by electrodeposition technique. The distirbution of the pattern of the pores can be altered by varying the process parameters such as anodization duration, electrolyte concentration, temperature, and anodization potential in a two step anodization. We have performed quantitative analysis of the influence of process parameters on distribution and sizes of ordered pores using Fourier transform (FFT) analyses

Electrodeposition of metal Nanorods on Alumina Templates

Electrodeposition is the process of depositing metal ions from the solution on to the cathode surface. Electrodeposition is a simple and efficient technique in fabricating various metal, metal oxide and semiconducting nanostructures. We have developed metal nanostructures such as gold, silver and copper using porous anodized alumina by electrodeposition techniques. We also fabricated nickel and cobalt oxide nanostructures using the above technique. Currently we are involved in the development of semiconducting nanostructures.

All the metallic nanopillar array structures we developed can withstand aqueous interaction forces. We also demonstrated that these nanopillar arrays do not exhibit any deformation after the electrochemical processes. We observed about 8 times increase in steady state current output in gold nanopillar arrays with respect to the flat surface gold electrode. These results show that these nanopillar array structures are viable for use in high sensitivity sensors.

We use Scanning Electron microscope and Transmission Electron microscope to study the nano structures developed. We also have a Atomic Force Microscopy instrument (CP -Research) which we use for obtaining the surface morphology of nanostructures.

We are presently using the AFM for developing nanostuctures using the nanolithography techniques capable with the instrument.