Efficient methanol steam reforming over ZnCeZrOx: the unique role of cerium

Abstract

Metal oxide catalysts have been widely used in steam reforming of methanol (SRM), but they face the challenge of long-term running. Herein, we report a ZnCeZrO_x catalyst that can operate in SRM stably at 400 °C. The H₂ production rates of Zn₁Ce_yZr₉O_x catalysts are estimated to be in the range of 103.8 to 109.5 μmol_H2 g_cat⁻¹ s⁻¹ with methanol conversion rates varying in the range of 93.6% to 99.8% at a WHSV of 4.5 h⁻¹. The enhanced activity and stability of the ZnZrO_x solid solution catalyst is mainly attributed to the large number of oxygen vacancies for water activation and the stable solid solution structure induced by Ce doping. This work indicates that matched rates for H₂O and methanol activation are essential in SRM.