Embedded‐Type Cu Nanoparticle with Largely Enhanced Catalytic Activity and Stability Toward Methanol Steam Reforming

Abstract

Abstract Hydrogen production through low‐temperature methanol steam reforming (MSR) reaction plays a critical role in the development of new energy but remains a great challenge. Herein, we report a Cu/Zn(Ga)O x catalyst, which is prepared via an interface reconstruction strategy. Interestingly, this catalyst is featured with a unique mortise‐and‐tenon structure: Cu nanoparticles are embedded into the Zn(Ga)O x substrate, which ensures a stable Zn–O–Cu + –O v –Ga δ + interface structure. The resulting Cu/Zn(Ga)O x catalyst exhibits 99.3% CH 3 OH conversion with an H 2 production rate of 124.6 µmol g cat −1  s −1 at 225 °C, which is preponderant to the state‐of‐the‐art catalysts. Furthermore, an ultra‐high catalytic stability was demonstrated through a 400 h stream‐on‐line test without obvious decline. Kinetic isotope analysis, in situ spectroscopy characterizations, and theoretical calculations reveal that the MSR reaction over Cu/Zn(Ga)O x catalyst follows the formaldehyde oxidation route. The CH 3 O* and H 2 O molecule adsorb at the adjacent Cu + −O v interface (intrinsic active site) with an oxygen‐terminal adsorption configuration, which promotes electron transfer from the d ‐band center of Cu to the O ( s , p )‐band of the substrate molecule. This significantly reduces the energy barrier of C─H bond cleavage in CH 3 O* dehydrogenation (the rate‐determining step) and H 2 O dissociation, accounting for the extraordinarily enhanced H 2 production.