Bromine-mediated electrochemical propane dehydrogenation by self-assembled ionic liquid-SnO 2 hollow spheres

Conventional thermal propane dehydrogenation (PDH) faces several notable drawbacks, including high energy requirements, coking-induced catalyst deactivation, and the need for product separation. An electrocatalytic approach, using self-assembled ionic liquid (IL)–tin dioxide (SnO 2 ) hollow spheres as the electrocatalyst, enables efficient PDH at ambient temperature. In this process, bromopropane formed in the anolyte from propane reacts with hydroxyl anions from the cathode to yield propene. The propene selectivity exceeds 98%, and the continuous production of high-purity (>99%) propene gas from the anolyte eliminates the need for downstream separation. The IL-SnO 2 catalyst maintains its activity and selectivity for more than 6000 hours, with a small voltage increase rate of 3.16 microvolts per hour. Mechanistic studies suggest that the IL layer enhances propane adsorption and facilitates the carbon-hydrogen bond activation step on adjacent Sn sites. After reaction, the IL layer promotes propene desorption and suppresses deep dehydrogenation.