"Spicy world of NanoScience"
Sujith Kalluri, Asha A.M, Anjali P, Vani R, Sivakumar N, K. R. V. Subramanian, A.Sreekumaran Nair, Shantikumar V Nair*, A. Balakrishnan*
Nano Solar Division, Amrita Center for Nanosciences and Molecular Medicine, Kochi, India 682 041
The present study is the first example for use of a commercially available polyaniline-carbon black composite to develop highly porous and conductive nanofiber mats via electrospinning using an optimized amount of polyvinyl alcohol as a carrier solution, which was calcined at 230 ⁰C to attain a stable conducting nanofiber network. Ultra-violet spectroscopy was used to determine the refractive index values for porosity measurements and showed an increase in porosity from 42±1.8% to 73±5% after heating. The extraction of PVA was confirmed by Fourier transform infrared spectroscopy. The spatial specific conductance mapping using Scanning Electro-Chemical Microscopy showed that the presence of insulating carrier solution could introduce percolation threshold. The heat-treated fibers showed four folds increase in specific conductance when compared to as-prepared fibers. It is hypothesized that the presence of a nanoscale Schottky contacts between “metallic” carbon black in the polymer matrix and “semiconducting” PANI, which play a key role in determining conducting pathways. It can find wide applications in the area of dye-sensitized solar cells as photocathodes, supercapacitors and nanoscaled electronic devices.