Bifunctional core-shell architecture allows stable H2 production utilizing CH4 and CO2 in a catalytic chemical looping process

Abstract

We report on the development of a bifunctional catalyst (Pt) - oxygen carrier (Fe2O3) that integrates the dry reforming of methane (DRM) into the chemical looping-based production of hydrogen. The material exhibits a high and stable methane conversion (˜ 80%) and hydrogen yield (10.8 mmol/g catalyst-oxygen carrier) with only a small quantity of impurities (CO, CO2 <2 ppm). The structural changes of the material are followed by operando X-ray powder diffraction and X-ray absorption spectroscopy coupled with gas chromatography. Insight into the evolution of the size of the Pt nanoparticles and their interaction with CeO2 are probed by transmission electron microscopy and X-ray absorption fine structure analysis. Under DRM conditions, the Pt nanoparticles grow in size, however, their re-dispersion on the CeO2 support (via PtOx-support interaction) during air oxidation recovers their activity in the consecutive cycle.