Study of the Role of Surface Oxygen Functional Groups on Carbon Nanotubes in the Selective Oxidation of Acrolein

Carbon nanotubes (CNTs) are promising candidates for metal-based catalysts in the selective catalytic oxidation of acrolein. It has been proposed that the surface functional groups play an important role in this reaction. We employ the simple calcination and reduction method to selectively remove the oxygen functional groups on the CNT surface. With the assistance of different characterization techniques such as temperature-programmed desorption and X-ray photoelectron spectroscopy, epoxy and lactone oxygen groups on the CNT surface are recognized as the active sites for acrolein selective oxidation. Through adjusting the amount of epoxy and lactone groups, a top catalytic performance (51.2% acrolein conversion and 79.7% acrylic acid selectivity) is achieved. Our results indicate that CNTs can be selectively functionalized and used as catalysts for the selective oxidation reaction.