Porosity effect on ZrO2 hollow shells and hydrothermal stability for catalytic steam reforming of methane

Abstract

Hydrogen is an emerging energy source/carrier for oil refining and fuel cell applications. The development of an efficient and stable catalyst to produce hydrogen-rich gas is required for industrial application. The Ni@yolk-ZrO₂ catalyst could be a potential solution to tackle the challenges in hydrogen production. The catalyst was characterized using a combination of XRD, TEM, AAS, TPR, BET, and XPS. In this study, the amount of micropores in ZrO₂ hollow shells was demonstrated to influence the catalytic performance. Ni@yolk-ZrO₂ catalysts were evaluated for 48 hours under steam reforming of methane and their porosity effect in ZrO₂ hollow shells was identified. From the characterization of BET and catalytic evaluation, the physical information of the ZrO₂ hollow shell was established, which affected the catalytic performance in steam reforming of methane. Furthermore, the results from XPS and TEM showed that Ni particles were controlled under a ZrO₂ yolk–shell structure framework and showed the characteristic of moderately strong hydrothermal stability after the steam reforming test. The catalysts were studied at a GHSV of 50 400 mL g_cat⁻¹ h⁻¹ and S/C = 2.5 at 750 °C and they remained stable with methane conversion more than 90% for 48 hours.