High-Performance Co-production of Electricity and Light Olefins Enabled by Exsolved NiFe Alloy Nanoparticles from a Double-Perovskite Oxide Anode in Solid Oxide-Ion-Conducting Fuel Cells

作者：Tan, Ting; Wang, Ziming; Huang, Kevin^*; Yang, Chenghao^*

来源：ACS Nano, 2023, 17(14): 13985-13996.

DOI：10.1021/acsnano.3c03956

• in situ exsolution
• double perovskite
• propane conversion
• light olefins
• electrochemicalreactors

Light olefins (LOs) such as ethylene and propylene arecriticalfeedstocks for many vital chemicals that support our economy and dailylife. LOs are currently mass produced via steam cracking of hydrocarbons,which is highly energy intensive and carbon polluting. Efficient,low-emission, and LO-selective conversion technologies are highlydesirable. Electrochemical oxidative dehydrogenation of alkanes inoxide-ion-conducting solid oxide fuel cell (SOFC) reactors has beenreported in recent years as a promising approach to produce LOs withhigh efficiency and yield while generating electricity. We reporthere an electrocatalyst that excels in the co-production. The efficientcatalyst is NiFe alloy nanoparticles (NPs) exsolved from a Pr- andNi-doped double perovskite Sr2Fe1.5Mo0.5O6 (Pr0.8Sr1.2Ni0.2Fe1.3Mo0.5O6-& delta;, PSNFM) matrixduring SOFC operation. We show evidence that Ni is first exsolved,which triggers the following Fe-exsolution, forming the NiFe NP alloy.At the same time as the NiFe exsolution, abundant oxygen vacanciesare created at the NiFe/PSNFM interface, which promotes the oxygenmobility for oxidative dehydrogenation of propane (ODHP), coking resistance,and power generation. At 750 & DEG;C, the SOFC reactor with the PSNFMcatalyst reaches a propane conversion of 71.40% and LO yield of 70.91%under a current density of 0.3 A cm(-2) without coking.This level of performance is unmatchable by the current thermal catalyticreactors, demonstrating the great potential of electrochemical reactorsfor direct hydrocarbon conversion into value-added products.