Effect of the Anode Structure on the Stability of a Direct Methanol Fuel Cell

Abstract

The stability of a direct methanol fuel cell (DMFC) was investigated by two single DMFCs with different anode structure membrane electrode assembly (MEA) under discharging at the constant current model for more than 4000 h. One of the MEAs with a catalyst coating membrane (CCM) anode electrode loads 5.5 mg cm–2 anode catalyst of Ru black loading, and the other with a gas diffusion layer coating (GDE) anode electrode loads 5.5 mg cm–2 of 60% PtRu/C. During the stability testing, DMFC with a CCM anode structure with a noble metal loading (5.5 mg cm–2) showed a 22% performance loss and that of GDE anode structure with a lower noble metal loading (3.3 mg cm–2) was 17%. Polarization curves, electrochemical measurements, and EDX (energy dispersive X-ray spectroscopy) were performed to analyze the difference of catalyst activity, internal resistance, and Ru loss between two DMFCs.

Polypyrrole nanowires as a cathode microporous layer for direct methanol fuel cell to enhance oxygen transport

“…The accumulated methanol in the cathode resulting from methanol crossover poisons the platinum catalyst, so the voltages reduce 48 . At open circuit potential, the accumulated methanol in cathode is oxidized by oxygen and the voltages recover 49 . The average voltages of the DMFC with PPy‐20 are 518.6 and 495.2 mV at the first and fifth intermittent discharge, respectively, and the cell voltage decreases 23.4 mV.…”

“…48 At open circuit potential, the accumulated methanol in cathode is oxidized by oxygen and the voltages recover. 49 The average voltages of the DMFC with PPy-20 are 518.6 and 495.2 mV at the first and fifth intermittent discharge, respectively, and the cell voltage decreases 23.4 mV. For the CB-40, 23.2 mV of the cell voltage is lost (489.9 and 466.7 mV at the first and fifth intermittent discharge, respectively).…”

Enhanced proton transport properties of sulfonated polyarylene ether nitrile (SPEN) with moniliform nanostructure UiO-66-NH2/CNT

“…Methanol is used as a fuel to flow from the anode to the cathode of the fuel cell and undergoes electrochemical oxidation reaction to produce protons by the action of catalyst in the DMFCs. [46][47][48][49] However, methanol permeation inevitably occurs during fuel cell operation. The Zheng et al 9…”

Enhanced Methanol Electro‐Oxidation Activity of Nanoclustered Gold

“…Another challenge is to maintain good catalyst stability at low loadings under DMFC operating conditions. [ 4 ] For example, Pt is strongly poisoned by the accumulation of the methanol electro‐oxidation (MEO) reaction residues such as COH and CO on its surface, compromising the device durability. [ 5 ] Switching from an acid electrolyte to an alkaline one and/or making combinations with oxophilic components enhances Pt activity, given that the presence of adsorbed OH accelerates the CO oxidation step.…”