NiO nanosheet array integrated monoliths for low temperature catalytic propane oxidation: A study on the promotion effect of Ce doping

Abstract

Constructing robust catalysts by growing nanostructure arrays directly onto honeycomb monoliths is a promising technology for fabricating highly active reactors with low materials usage and cost-effectiveness. In this study, catalytically active NiO nanosheet arrays were uniformly grown onto the channel surfaces of cordierite honeycombs to form monolithic catalysts with ultra-low loading. Ce doping was found to significantly enhance the catalytic propane oxidation performance of pristine NiO nanosheet arrays. With a Ce doping of ∼4 wt.% in NiO, a conversion of 90 % propane oxidation into CO2 was achieved at 440 °C, a ∼40 °C decrease compared to the pristine NiO under a space velocity of 24,000 h−1. With the promoting effect of Ce, the Ce-doped NiO nanosheet arrays exhibited a much better thermal stability, with only 1.1 % loss of conversion after a 48 h operation at 425 °C, in comparison with a 21.5 % loss over the pristine NiO catalyst.