Abstract
Purification/separation of CO 2 stream from carbon capture or other carbon source is highly energy consuming process. However, oxidative impurity of O 2 either deactivates catalysts in most carbon reduction systems, and thus reduces CO 2 conversion efficiency. Here we report an effective method for splitting O 2-containing CO 2 into CO, through a chemical looping scheme with Cu (5 at%) doped LaFeO 3 perovskites as efficient oxygen carriers. Up to 2.28 mol/kg CO yield was achieved with high stability in the presence of O 2, five times higher than that with the state-of-the-art oxygen carrier, while pristine LaFeO 3 perovskite only showed efficient capability of reducing pure CO 2. Furthermore, the syngas productivity was doubled with Cu modification. Through experimental characterizations and ab initio calculations, we uncovered that the exsolution of metallic Cu on the surface of reduced perovskite was able to mitigate the competition between CO 2 and O 2 in the re-oxidation step. We envision that the efficient CO 2 splitter with well-designed oxygen carriers have the potential to facilitate economical combination of impure carbon feedstock and carbon utilization system.
Original language | English |
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Article number | 105320 |
Journal | Nano Energy |
Volume | 78 |
Early online date | 13 Sept 2020 |
DOIs | |
Publication status | Published - Dec 2020 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2020
Funding
This work was supported by the National Natural Science Foundation of China (Nos. 51774159 and 21706108), the Yunnan applied basic research projects (No. 2018FD032), and the Qinglan Project of Kunming University of Science and Technology. The work of X.B.L. and X.C. was supported by the Center for Advanced Materials for Energy and Environment. X.B.L. acknowledges support from the China Scholarship Council (CSC) graduate scholarship.
Keywords
- CO reduction
- Chemical looping
- Oxygen impurity
- Perovskite nanocomposites