Comparative Studies of Oxygen Reduction Reaction and Ethanol Oxidation Reaction on PtSn/C and PtNi/C Catalysts.

摘要

In this work were used Sn and Ni as second metals with Pt to study both the electrochemical oxidation of ethanol using "in situ" ATR-FTIR and the oxygen reduction reaction which is assessed using a rotating ring disk electrode technique (RRDE). The onset potential of ethanol oxidation is 0.3 V for PtSn/C, and 0.4 V for PtNi/C. Acetic acid is the main product formed using PtSn/C while using PtNi/C CO2 is the main product. The current densities for ORR using PtSn/C were similar to those ones using PtNi/C in all potential regions, including the region of limit diffusion current. However, the peroxide production was smaller for PtNi/C than PtSn/C between -0.1 to -0.5 V. For PtNi/C, the reaction proceeds through the transfer of 3.7 electrons, while for PtSn/C about 3.8 electrons.