Abstract
Non-noble metal catalysts for promoting the sluggish kinetics of oxygen evolution reaction (OER) are essential to efficient water splitting for sustainable hydrogen production. Birnessite has a local atomic structure similar to that of an oxygen-evolving complex in photosystem II, while the catalytic activity of birnessite is far from satisfactory. Herein, we report a novel Fe-Birnessite (Fe-Bir) catalyst obtained by controlled Fe(III) intercalation- and docking-induced layer reconstruction. The reconstruction dramatically lowers the OER overpotential to 240 mV at 10 mA/cm2 and the Tafel slope to 33 mV/dec, making Fe-Bir the best of all the reported Bir-based catalysts, even on par with the best transition-metal-based OER catalysts. Experimental characterizations and molecular dynamics simulations elucidate that the catalyst features active Fe(III)-O-Mn(III) centers interfaced with ordered water molecules between neighboring layers, which lower reorganization energy and accelerate electron transfer. DFT calculations and kinetic measurements show non-concerted PCET steps conforming to a new OER mechanism, wherein the neighboring Fe(III) and Mn(III) synergistically co-adsorb OH∗ and O∗ intermediates with a substantially reduced O-O coupling activation energy. This work highlights the importance of elaborately engineering the confined interlayer environment of birnessite and more generally, layered materials, for efficient energy conversion catalysis.
Original language | English (US) |
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Pages (from-to) | 11215-11226 |
Number of pages | 12 |
Journal | Journal of the American Chemical Society |
Volume | 145 |
Issue number | 20 |
DOIs | |
State | Published - May 24 2023 |
Bibliographical note
Funding Information:This work was supported by the National Natural Science Foundation of China (21972006, U2001217, 22261160370), Shenzhen Peacock Plan (KQTD2016053015544057), and Shenzhen Science and Technology Innovation Commission (JCYJ20190808155413194).
Publisher Copyright:
© 2023 American Chemical Society.
PubMed: MeSH publication types
- Journal Article