Molten-salt synthesis of porous La0.6Sr0.4Co0.2Fe0.8O2.9 perovskite as an efficient electrocatalyst for oxygen evolution
The development of an efficient and low-cost electrocatalyst for the oxygen evolution reaction (OER) via an eco-efficient route is a desirable, although challenging, outcome for overall water splitting. Herein, an iron-rich La0.6Sr0.4Co0.2Fe0.8O2.9 (LSCF28) perovskite with an open porous topographic structure was developed as an electrocatalyst by a straightforward molten-salt synthesis approach. It was found that porosity correlates with both the iron content and the molten-salt approach. Benefiting from the large surface area, high activity of the porous internal surface, and the optimal electronic configuration of redox sites, this inexpensive material exhibits high performance with a large mass activity of 40.8 A·g–1 at a low overpotential of 0.345 V in 0.1 M KOH, surpassing the state-of-the-art precious metal IrO2 catalyst and other well-known perovskites, such as Ba0.5Sr0.5Co0.8Fe0.2O3 and SrCoO2.7. Our work illustrates that the molten-salt method is an effective route to generate porous structures in perovskite oxides, which is important for energy conversion and storage devices.
Keywordsiron-rich perovskite oxygen evolution reaction energy storage and conversion molten salt
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We thank Hong-Ji Lin and Chien-Te Chen’s help for the Soft X-ray absorption spectroscopy experiments in National Synchrotron Radiation Research Center (NSRRC). This work was partly supported by the National Natural Science Foundation of China (Nos. 11305250 and 11575280), the Joint Funds of the National Natural Science Foundation of China (No. U1232117), the Key Project of Science and Technology of Shanghai (No. 15DZ1200100), and the Youth Innovation Promotion Association of the Chinese Academy of Sciences (Nos. 2014237 and 2015212).
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