High purity H2 resource from methanol steam reforming at low-temperature by spinel CuGa2O4 catalyst for fuel cell

Abstract

Methanol steam reforming (MSR) is an effective way to provide high purity hydrogen for PEMFCs, however the main challenge is the toxic effect of CO. In this study, CuGa₂O₄ spinel catalyst was applied first for MSR at low temperature. The properties of catalysts were characterized by various techniques, the MSR catalytic performance was also studied in deeply. The surface of the catalyst is composed of particle chains that are interconnected, forming high-volume pores that increase the specific surface area. The catalyst also has a rich porous structure, exposing more active sites. Furthermore, the presence of oxygen vacancies facilitates the adsorption of reactive oxygen species, reducing CO generation. A possible pathway for methanol dehydrogenation has been determined using DFT calculations. The relatively low overall energy barrier on the catalyst surface facilitates methanol activation. Among the steps, formaldehyde dehydrogenation is the rate-determining step in the methanol dehydrogenation process. The CuGa₂O₄ catalyst exhibits good gas selectivity, with a hydrogen selectivity of 98 % and CO selectivity of 0. and no deactivation occurred within 50 h, demonstrating outstanding durability. These features allow it to serve as an efficient catalyst for MSR online hydrogen production and direct supply to PEMFCs.