One Dimensional Compounds of Mo/W for Electrochemical Applications. B.Viswanathan*, J.Rajeswari and P.S.Kishore National Centre for Catalysis Research, Indian Institute of Technology- Madras, Chennai , India Introduction  The development of new materials that can solve the challenging problems in the areas of clean energy production, conversion and storage is of paramount importance in the quest to find an alternative to environmentally unfriendly fossil-fuel use.  One-dimensional (1D) nanostructures such as nano-tubes and nano-wires have attracted special attention due to their unique physical properties and their potential applications in different nanodevices 1. Despite the promising achievements and plausible prospects of fuel cells, Pt and Pt-Ru remain to be the best electro-catalysts so far.  In the electrochemical generation of pure hydrogen, there are attempts to replace the Pt catalysts. The present study examines the possibility of employing low cost metal oxides and metal sulfide nanomaterials for energy conversion applications. The scope is to synthesize nanorods and load active metal and examine them as electrodes for DMFC, ORR and Hydrogen evolution reactions. Reference Abstract  For methanol oxidation and also for ORR the catalysts studied can be ranked as follows: Pt/WO 3 nanorods >Pt-Ru/C (J. M) > Pt/ bulk WO 3. Hydrogen evolution reaction and oxygen reduction reaction on various electrodes with and without WO 3 NR have shown that high activity. In general it could be concluded that 1-D nanorods of WO 3 and MoS 2 nanomaterials are better candidates than their bulk counterparts Fig. 1. XRD patterns of (a) as –synthesized Fig 2. TEM of nano rods of MoO 2 + WO 3 Fig 3. Cyclic voltammograms of (a) 20% Pt/WO 3 NR, (b) 20% Pt-Ru/C (J. M) and (c) 20% Pt/WO 3 B in 1MCH 3 OH- 1M H 2 SO 4 at a scan rate of 25mVs -1 Fig. 4 Linear sweep voltammograms of (A): (a) WO 3 NR, (b) WO 3 B and (c) bare glassy carbon electrode. Table. 1 Comparison of electro- catalytic activity of Pt supported on various supports for methanol oxidation Table. 2 Comparison of electro-catalytic activity of Pt on various carbon supports for methanol oxidation It is seen that WO 3 nanorods can replace Ru in Pt-Ru catalysts for methanol oxidation in fuel cells. The activity of the electrocatalysts is enhanced when WO 3 NR or CNT are used as supports. ORR revealed that Pt/WO 3 NR-C was more active than other systems studied. Current density (mAcm -2 ) Specif capacitance F.g - 1 WO 3 NR Specif capacitance F.g - 1 WO 3 -B Electro catalystsHER activity (mAcm -2 ) 20%Pt/WO 3 NR-C 20%Pt/WO 3 B-C 20%Pt/C Table.5 HER activity of various platinum containing catalysts HER activity for Pt on WO 3 NR is hgiehr than that on bulk WO 3. The electrode on nanorod has a lower Tafel slope and high exchange current density. MoS 2 nanotubes are better as they show lower over potential and high current density when compared to WO 3 nanorods 20%ElectrocatalystC DMA 20% Pt/WO 3 NR-CNT 20% Pt/WO 3 NR-C 20% Pt/C Pt/WO 3 B Electro-catalystC DMA 20%Pt/WO 3 NR 20%Pt-Ru/C(J. M) Table. 4 Specific capacitance at different current densities Pseudocapacitance is due to the combination of hydrogen adsorption/desorption. The cycling performance for checked for 40 cycles. Current charge –discharge studies show that WO 3 and MoO 2 nano rods constitute better alternates for the high cost Ru-base electrodes for capacitor applications Results Conclusion One dimensional nano rods of oxides and sulphides of metals (M = W and Mo ) are alternate supports for Pt In DMFC and ORR applications. They have been examined for their catalytic behavior for hydrogen evolution reaction and super capacitor applications. Acknowledgement The authors thank DST, Government of India for supporting the National Centre for Catalysis Research. 1. Duan, X. F. andLieber,C.M., Adv. Mater. 2000, 12, Che, M., Fournier,M. and Launay, J.P., J. Chem. Phys.1979, 71, Chemseddine, A., Sanchez,C., Livage, J., Launay, J.P. and Fournier,M.,Inorg. Chem. 1984, 23, Manoharan, R. and Prabhuram, J., J. Power Sources, 2001, 96, Rajesh, B., Karthik, V., Karthikeyan, S., Ravindranathan Thampi, K., Bonard, J.M., Viswanathan, B., Fuel, 2002, 81, 2177– Rajesh, B., Ravindranathan Thampi, K., Bonard, J.M., Xanthopoulos, X., Mathieu, H..J., and Viswanathan, B., J. Phys. Chem. B, 2003, 107, *