A direct methanol fuel cell based on a novel low-cost nanoporous proton-conducting membrane

We report here a low-cost and improved direct methanol fuel cell (DMFC), based on a novel nanoporous proton-conducting membrane (NP-PCM). The use of the NP-PCM in DMFC offers several advantages over the Nafion-based DMFC; lower membrane cost (by more than two orders of magnitude), smaller pores (by a factor of two), and lower methanol crossover (by up to an order of magnitude), which lead to much higher fuel utilization. The NP-PCM also has higher conductivity (by up to four times). In addition, the ionic conductivity of the NP-PCM, unlike Nafion, is not affected by heavy metal impurities, thus it may permit the use of cheaper catalysts and hardware materials. The maximum power density achieved so far, at 80 degreesC and at ambient oxygen pressure, is 85 mW/cm(2) (obtained at 0.35 A/cm(2)). (C) 2000 The Electrochemical Society. S1099-0062(00)06-074-0. All rights reserved.