Low-temperature carbon combustion over proton conductor + electrocatalyst-mixed powders

Catalytic carbon combustion is a potential approach for eliminating particulate matter emissions from diesel engine vehicles. In this study, we report low-temperature carbon combustion by active oxygen formed at the interface of the mixed powders of a proton conductor (Sn0.9In0.1P2O7) and electrocatalyst (Pt or Mo2C). In a gaseous mixture of H2O and O2, H2O dissociated into protons and electrons at an anodic site of the interface and the resultant active oxygen oxidized carbon to CO2. Separately, O2 reacted with protons and electrons to form H2O at a cathodic site of the interface, resulting in formation of a local electrochemical cell at the proton conductor–electrocatalyst interface, which then self-discharged. This series of reactions could successfully reduce the ignition temperature for carbon to 200 °C for Pt and 300 °C for Mo2C.

Figure optionsDownload as PowerPoint slideResearch highlightsA mixed catalyst consisting of proton conducting Sn0.9In0.1P2O7 and electrocatalytically active Pt has at least ten times higher turnover frequency for Pt in the commonly used Pt/γ-Al2O3 catalyst.