Effect of Temperature on the Oxygen Reduction Reaction at Nitrogen-doped Carbon Nanotubes for Fuel Cell Cathode

摘要

One of the technical challenges in the area of fuel cell technology in this century is related to cost reduction on the fuel cell components especially the electrocatalysts. The doping of nitrogen as the n-type dopant have been shown to exhibit catalytic activity towards ORR and can be a good alternative to the precious metal with proper modifications. In order to optimize the efficiency of fuel cell, intermediate cell temperature are usually used. In this study, the effects of the temperatures towards ORR were studied over the temperature range of 298 - 343 K in 0.5 M H2SO4 on the metal-free nitrogen-doped carbon nanotubes (NCNT) using a thin-film rotating-ring disk electrode (RRDE). The NCNT catalysts were synthesised via chemical vapour deposition with ethylenediamine and iron phthalocyanine and post-treatment process was carried out prior to the analysis. The results showed that the ORR activity on NCNT has achieved its optimum value at 50 °C, beyond which the activity was decreased. Therefore, NCNT should be modified by compositing with other metal or non-metal to improve its activity at higher temperature.