Multi-scale designed CoxMn3–xO4 spinels: Smart pre-catalysts towards high-efficiency pyrolysis-catalysis recycling of waste plastics

• Published in: Applied catalysis. B, Environmental Environmental, 2023-05, Vol.324, Article 122271
• Main Authors: Liu, Xingmin, Xu, Dan, Ding, Hui, Widenmeyer, Marc, Xie, Wenjie, Mellin, Maximilian, Qu, Fangmu, Chen, Guoxing, Zhang, Ye Shui, Zhang, Zhenyu, Rashid, Aasir, Molina-Luna, Leopoldo, Hofmann, Jan P., Riedel, Ralf, Brett, Dan J.L., Weidenkaff, Anke
• Format: Article
• Language: English
• Subjects: Carbon nanotube composites; CoxMn3–xO4 spinels; H2 production; Pyrolysis-catalysis; Waste plastics
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2022.122271

In this work, multiscale designed 3-dimensional (3D) rose-like CoxMn3–xO4 spinel smart pre-catalysts that can self-convert into the targeted active site-rich Co/MnO catalysts were developed for the high-efficiency conversion of waste plastics. At a pre-catalyst to plastic weight ratio of 1:14, the carbon nanotube composites (CNCs) and H2 yield can reach 41 wt% and 36 mmol·g˗1pla., while the specific CNCs and H2 yield can be as high as 7.48 g˗1cat. and 634 mmol·g˗1pla.·g˗1cat. The latter is more than one order of magnitude higher than reported in the literature. Density functional theory calculations indicate that the Co/MnO catalyst exhibits excellent activity in the dissociation of alkanes (e.g., CH4). The resulting CNCs demonstrated excellent discharge capability and extended cycling performance when used as a lithium-ion battery anode. This work revealed an innovative recipe and novel insight for developing advanced catalyst materials as the next generation catalysts for the conversion of waste plastics. [Display omitted] •Self-conversion of multiscale designed smart pre-catalysts into active-site-rich Co/MnO catalysts to recycle waste plastics.•The physical mechanism of superior catalytic performance of Co/MnO is pinpointed via DFT calculation.•The specific carbon nanotube composites and H2 yield of the Co/MnO catalyst reach a new record high.•The plastic converted carbon nanotube composites were tested to be excellent anode materials for lithium-ion batteries.