Catalytic and electrocatalytic production of H 2 from the water gas shift reaction over Pd in a high temperature proton-conducting cell-reactor

Abstract

The water gas shift reaction (WGS) was studied in a proton-conducting cell-reactor at 873–1023 K and atmospheric total pressure. The proton conductor was a strontia–zirconia–yttria perovskite disk of the form: SrZr 0.95Y 0.05O 3 − α . A polycrystalline palladium film was used as the working electrode-catalyst. The reaction kinetics were evaluated with the cell operating under open circuit. Under closed circuit and with protons “pumped” away from the catalyst, the rate of H 2 formation increased to a moderate extent. The Faradaic efficiency ( Λ) was found to attain values as high as Λ = 8, while the highest rate enhancement ratio ( ρ) measured was ρ = 2. The Proton Transport Number (PTN) varied between 0.40 and 1.0.