Ga ₂ O ₃ -Modified Cu–ZnO Catalysts for Efficient Hydrogen Production from Aqueous-Phase Reforming of Methanol

Ensuring safer and more satisfactory hydrogen (H 2 ) production from aqueous-phase reforming of methanol (APRM) is crucial for automotive, marine, and aerospace applications. However, nonprecious metal catalysts face challenges in realizing efficient methanol (CH 3 OH) dehydrogenation and effective carbon monoxide (CO) suppression for APRM without a strong base. In this work, we synthesized Ga 2 O 3 -modified Cu–ZnO catalysts with carbon encapsulation, leading to a uniform Cu dispersion. The optimized 12 wt % GCZ-2.0-C450 catalyst exhibits good performance over a wide temperature range (130–210 °C). It achieves a high H 2 production rate of 101.2 μmol/g cat /s and low CO selectivity (0.07%) at 210 °C with long-term stability, surpassing the reported Cu- and Pt-based catalysts in APRM. Density functional theory calculations indicate that the Ga 2 O 3 introduction significantly reduces the Gibbs energy of the rate-determining step of *CH 3 O + *H → *CH 2 O + *H 2, dropping from 1.25 to 0.60 eV. Meanwhile, the adsorption energy of the generated *H 2 decreases from −2.92 to −0.13 eV, which facilitates the release of gaseous H 2 .