Electro-oxidation of hydrolysed poly-oxymethylene-dimethylether on PtRu supported catalysts

Poly-oxymethylene-dimethylether (CH3-O-(CH2-O)n-CH3 (n = 3), abbreviated as POMM3), which has no toxicity and a very low vapour pressure, unlike methanol, was investigated as a possible liquid fuel for a direct oxidation-type fuel cell. The electrocatalytic activity towards the oxidation of methanol, formaldehyde and a fully hydrolysed form of POMM3 in 0.1 mol dm−3 HClO4 solution was examined from 30 °C to 90 °C by using a channel flow cell system at three different types of PtRu catalysts, dispersed on high surface area supports, i.e., carbon black, antimony-doped tin oxide (Sb-SnO2), and the latter mixed with a certain fraction of acetylene black (AB) to improve the electronic conductivity. The PtRu/Sb-SnO2 + AB catalyst exhibited the best electrocatalytic activity and thermal stability towards the fully hydrolysed POMM3 and formaldehyde oxidations, for which the mass activity was about ten times higher than that for methanol.