Hydrogen Production Mechanism in Low-Temperature Methanol Decomposition Catalyzed by Ni<sub>3</sub>Sn<sub>4</sub> Intermetallic Compound: A Combined Operando and Density Functional Theory Investigation
Silvia Mauri, Gianluca D’Olimpio, Corneliu Ghica, Luca Braglia, Chia‐Nung Kuo, Marian Cosmin Istrate, C. S. Lue, L. Ottaviano, Tomasz Klimczuk, Danil W. Boukhvalov, Antonio Politano, Piero Torelli
Abstract
Hydrogen production from methanol decomposition to syngas (H 2 + CO) is a promising alternative route for clean energy transition. One major challenge is related to the quest for stable, cost-effective, and selective catalysts operating below 400 °C. We illustrate an investigation of the surface reactivity of a Ni 3 Sn 4 catalyst working at 250 °C, by combining density functional theory, operando X-ray absorption spectroscopy, and high-resolution transmission electron microscopy. We discovered that the catalytic reaction is driven by surface tin-oxide phases, which protects the underlying Ni atoms from irreversible chemical modifications, increasing the catalyst durability. Moreover, we found that Sn content plays a key role in enhancing the H 2 selectivity, with respect to secondary products such as CO 2 . These findings open new perspectives for the engineering of scalable and low-cost catalysts for hydrogen production.