Process-intensified protonic ceramic fuel cells for power generation, chemical production, and greenhouse gas mitigation

Here, we present protonic ceramic fuel cells (PCFCs) that achieve the internal dry reforming of methane (DRM) at 550°C–650°C to simultaneously generate power, produce syngas or hydrogen as chemical building blocks, and to mitigate two harmful greenhouse gases. We developed an oxide-supported in situ exsolved Ni-Ru catalyst (Sm0.2Ce0.7Ni0.1Ru0.05O2-δ, i.e., SDC-Ni-Ru). The in situ exsolved Ru clusters favor the CO2 activation step, while the Ni clusters promote the CH4 activation. The synergy between Ni and Ru clusters simultaneously improves the CH4 and CO2 activation, enhancing the DRM activity. Additionally, we discovered that the Ru clusters alter the DRM pathway, favoring the formation of monodentate carbonate species, which subsequently accelerates the oxidization of −CH∗ species on Ni clusters and improves the coking tolerance. The PCFCs equipped with this SDC-Ni-Ru internal DRM catalyst attain exceptional and durable power densities using a mixture of CH4 and CO2 as the fuel, setting a record for DRM-PCFCs.