Polyol-synthesized Pt2.6Sn1Ru0.4/C as a high-performance anode catalyst for direct ethanol fuel cells

PtSnRu/C catalysts with different atomic ratios and metal loadings were prepared using a polyol process to improve the performance of direct ethanol fuel cells (DEFCs). The catalysts were characterized using transmission electron microscopy and X-ray photoelectron spectroscopy. The DEFC performance was evaluated using a single-cell test. The ethanol electro-oxidation process and anode products were analyzed using in situ Fourier-transform infrared spectroscopy (FTIRS), gas chromatography, and neutralization titration. The performance of the Pt2.6Sn1Ru0.4/C catalyst was better than those of the Pt3Sn1/C and Pt2Sn1Ru1/C catalysts. The carbon-supported Pt2.6Sn1Ru0.4 catalyst with a 60 wt% metal loading gave a maximum power density of 121 mW/cm2 at 90 °C. In situ FTIRS and anode product analysis indicated that ethanol was electro-oxidized to acetaldehyde, acetic acid, ethyl acetate, and CO2. The ethanol oxidation efficiency on the Pt2.6Sn1Ru0.4/C catalyst was higher than that on the Pt3Sn1/C catalyst. The activation energy of ethanol electro-oxidation at the anode and surface composition analysis indicated that interactions among the surface elements resulted in a lower apparent activation energy and greater ethanol electro-oxidation efficiency on the Pt2.6Sn1Ru0.4/C catalyst.

Graphical AbstractA polyol-synthesized 60 wt% Pt2.6Sn1Ru0.4/C catalyst achieved a maximum power density of 121 mW/cm2 at 90 °C, and ethanol was mainly electro-oxidized to acetic acid with a negligible amount of CO2.Figure optionsDownload as PowerPoint slide