Converting Carbon Dioxide into Carbon Nanotubes by Reacting with Ethane

The urgency to mitigate environmental impacts from anthropogenic CO₂ emissions has propelled extensive research efforts on CO₂ reduction. The current work reports a novel approach involving transforming CO₂ and ethane into carbon nanotubes (CNTs) using earth-abundant metals (Fe, Co, Ni) at 750 °C. This route facilitates long-term carbon storage via generating high-value CNTs and produces valuable syngas with adjustable H₂/CO ratios as byproducts. Without CO₂, direct pyrolysis of ethane undergoes rapid deactivation. The participation of CO₂ not only enhances the durability of the catalyst, but also contributes about 30 % of the CNTs production, presenting a viable solution to CO₂ challenges. The CNT morphology depends on the catalyst used. Co- and Ni-based catalysts produce CNT with a 20 nm diameter and micrometer length, whereas Fe-based catalysts yield bamboo-like structures. This work represents a pioneering effort in utilizing CO₂ and ethane for CNT production with potential environmental and economic benefits.