Perovskites are promising oxygen carriers for solar‐driven thermochemical fuel production due to higher oxygen exchange capacity. Despite their higher fuel yield capacity, La0.6Sr0.4MnO3perovskite materials present slow CO2‐splitting kinetics compared with state‐of‐the‐art CeO2. In order to improve the CO production rates, the incorporation of Cr in La0.6Sr0.4MnO3is explored based on thermodynamic calculations that suggest an enhanced driving force toward CO2splitting at high temperatures for La0.6Sr0.4Cr
Organic‐inorganic hybrid perovskite solar cells are susceptible to multiple influencing factors such as moisture, oxygen, heat stress, ion migration. Given the complex practical working conditions for solar cells, a fundamental question is how different failure mechanisms collaborate and substantially accelerate the device degradation. In this study, it is found that ion migration can accelerate the reaction between oxygen and methylammonium lead iodide perovskite in light conditions. This is suggested since regions with local electric fields suffer from more severe decomposition. Here it is reported that cesium ions (Cs+) incorporated in perovskite lattice, with a moderate doping concentration (e.g. 5%), can function as stabilizers to efficiently interrupt such a synergistic effect between oxygen induced degradation and ion migration while retaining the high performance of perovskite solar cells. Both experimental and theoretical results suggest that 5% Cs+ions incorporation simultaneously suppresses the formation of reactive superoxide ions () as well as ion migration in perovskites by forming additional energy barriers. This A‐site cations engineering is also a promising strategy to circumvent the detrimental effect of oxygen molecules in FA‐based perovskites, which is important for developing high‐efficiency perovskite solar cells with enhanced stability.
more » « less- Award ID(s):
- 1903962
- NSF-PAR ID:
- 10453221
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Energy Materials
- Volume:
- 11
- Issue:
- 8
- ISSN:
- 1614-6832
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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