Near 100% CO selectivity in nanoscaled iron-based oxygen carriers for chemical looping methane partial oxidation.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 31796744.
- Also identified by DOI 10.1038/s41467-019-13560-0 and PMC identifier 6890731.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Chemical looping methane partial oxidation provides an energy and cost effective route for methane utilization. However, there is considerable CO<sub>2</sub> co-production in current chemical looping systems, rendering a decreased productivity in value-added fuels or chemicals. In this work, we demonstrate that the co-production of CO<sub>2</sub> can be dramatically suppressed in methane partial oxidation reactions using iron oxide nanoparticles embedded in mesoporous silica matrix. We experimentally obtain near 100% CO selectivity in a cyclic redox system at 750-935 °C, which is a significantly lower temperature range than in conventional oxygen carrier systems. Density functional theory calculations elucidate the origins for such selectivity and show that low-coordinated lattice oxygen atoms on the surface of nanoparticles significantly promote Fe-O bond cleavage and CO formation. We envision that embedded nanostructured oxygen carriers have the potential to serve as a general materials platform for redox reactions with nanomaterials at high temperatures.