Microwave-assisted CO oxidation over LaNiO₃ and Ce-promoted LaNiO₃

Microwave-assisted catalytic reactions have been investigated for energy-efficient chemical processes. However, catalysts with comparatively high heating properties, activities, and economics have been developed with limited success. In this study, we investigated the catalytic properties of Ce addition to LaNiO₃ catalyst, which has high CO oxidation activity and high microwave heating properties. Ce-added catalysts exhibited high heating properties under microwave heating. Increasing the Ce content in the catalyst enhanced the dielectric loss factor, the ability to absorb microwaves and convert them to heat, and improved the microwave heating properties of the catalyst. The catalytic activity toward CO oxidation over Ce-added catalysts decreased in the order of La_0.8Ce_0.2NiO₃ > La_0.9Ce_0.1NiO₃ > LaNiO₃ at all oxygen partial pressures when compared to the same microwave power. To clarify the role of Ce addition, temperature programmed reduction (TPR) by H_{2 ,} CO, and XAFS measurements were performed. TPR results suggested that Ce promotes oxygen mobility and then affects both CO oxidation and microwave heating properties.