Leow, W. R., Lum, Y., Ozden, A., Wang, Y., Nam, D.-H., Chen, B., … Sargent, E. H. (2020). Chloride-mediated selective electrosynthesis of ethylene and propylene oxides at high current density. Science, 368(6496), 1228–1233. doi:10.1126/science.aaz8459
Chemicals manufacturing consumes large amounts of energy and is responsible for a substantial portion of global carbon emissions. Electrochemical systems that produce the desired compounds by using renewable electricity offer a route to lower carbon emissions in the chemicals sector. Ethylene oxide is among the world’s most abundantly produced commodity chemicals because of its importance in the plastics industry, notably for manufacturing polyesters and polyethylene terephthalates. We applied an extended heterogeneous:homogeneous interface, using chloride as a redox mediator at the anode, to facilitate the selective partial oxidation of ethylene to ethylene oxide. We achieved current densities of 1 ampere per square centimeter, Faradaic efficiencies of ~70%, and product specificities of ~97%. When run at 300 milliamperes per square centimeter for 100 hours, the system maintained a 71(±1)% Faradaic efficiency throughout.
This material is based on work supported
by the Ontario Ministry of Colleges and Universities (grant ORFRE08-034), Natural Sciences and Engineering Research Council
(NSERC) of Canada (grant RGPIN-2017-06477), Canadian Institute
for Advanced Research (CIFAR) (grant FS20-154 APPT.2378),
and University of Toronto Connaught Fund (grant GC 2012-13).
D.S. acknowledges the NSERC E. W. R. Steacie Memorial Fellowship
This is the author’s version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version was published in Science on Volume 368 and 20 June 2020, DOI: doi.10.1126/science.aaz8459