Polypyrrole nanowire networks as anodic micro-porous layer for passive direct methanol fuel cells

Polypyrrole nanowire networks (PPNNs), as anodic micro-porous layer (MPL) of passive direct methanol fuel cells (DMFCs), are grown in-situ on the surface of carbon paper through an electrochemical polymerization. Passive DMFC with the novel MPL achieves a 28.3% increment in maximum power density from 33.9 mW cm(-2) to 43.5 mW cm(-2) compared with the conventional layer with similar PtRu(1:1) loading of 2.0 mg cm(-2) and operating with 4 M methanol solution at 25 degrees C. When the PtRu loading is decreased to 1.0 mg cm(-2), the maximum power density of the DMFC still reaches 34.3 mWcm(-2), which shows a comparative value with the conventional layer. The enhanced performance should be ascribed to the introduction of PPNNs, significantly improves catalyst utilization and mass transfer of methanol on the anode. (C) 2014 Elsevier Ltd. All rights reserved.