Enabling alcohol as a hydrogen carrier using metal-organic framework-stabilized Ir-Sc bifunctional catalytic sites.

Alcohols are attractive portable chemical carriers of hydrogen thanks to their reversible dehydrogenation, but the hydrogen release reaction is thermodynamically unfavorable. Coupling the alcohol dehydrogenation to acetal formation can shift the reaction thermodynamics for hydrogen production. Here, we stabilized Ir 3+ and Sc 3+ in a metal-organic framework (MOF) for tandem catalysis. The Ir 3+ center bearing an α-hydroxybipyridine ligand catalyzes alcohol dehydrogenation, and the Sc 3+ Lewis acid site catalyzes acetal formation that allows further dehydrogenation to form esters. The bifunctional UiO-bpyOH-IrCp-Sc catalyst effectively converts ethylene glycol to ester and H 2 without producing CO.