in this paper, the effect of surface area of reaction layers in gas diffusion electrodes on oxygen reduction reaction was investigated. for this purpose, various amounts (0.1, 0.2, 0.3, 0.4, 0.5, 1, 1.5 and zero %wt of total loading of reaction layer) of single walled carbon nanotube (swcnt) were inserted in the reaction layer. the performance of gas diffusion electrodes for oxygen reduction re...