Ga <sub>2</sub> O <sub>3</sub> -Modified Cu–ZnO Catalysts for Efficient Hydrogen Production from Aqueous-Phase Reforming of Methanol
Minyi Lu, Yushen Liu, Fan Yang, Yuxin Ge, Xudong Shi, Yongqi Mao, Xinyuan Song, Zejian Li, Jiajin Li, Yuxiang Lyu, Guimei Liu, Zhuoyu Zheng, Yuan Yuan, Junwei Liao, Xitang Qian, Minhua Shao, Tiejun Wang
Abstract
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 .