A Composite Catalyst with a Lamellar Fe₃O₄/Pt/Fe₃O₄ Structure and Complementary Dual Catalytic Functions

A composite catalyst with a lamellar Fe₃O₄/Pt/Fe₃O₄ structure has been prepared from an Al₆₇Pt₇Fe₂₆ (at.%) alloy by leaching with an aqueous 10 % NaOH solution. The lamellar Fe₃O₄/Pt/Fe₃O₄ phase exhibits significant catalytic performance as measured by activity and selectivity during the steam reforming of methanol (SRM : CH₃OH + H₂O → CO₂ + 3H₂) superior to the catalytic performance of Pt obtained from Al₂Pt and a conventional impregnated Pt/Fe₃O₄ catalyst under the same reaction conditions. It is clear that the Pt and Fe₃O₄ were primarily responsible for the catalysis of the decomposition of methanol (DM : CH₃OH → CO + 2H₂) and the water gas shift reaction (WGSR : CO + H₂O ⇄ CO₂ + H₂), respectively. These two reactions work together in a complementary manner to facilitate the overall SRM reaction due to efficient the heat transfer characteristics of the lamellar Fe₃O₄/Pt/Fe₃O₄ structure. In this study, we demonstrate that a lamellar structure is available to couple two separate reactions to obtain a new catalytic function.