Defect Etching in Carbon Nanotube Walls for Porous Carbon Nanoreactors: Implications for CO2 Sorption and the Hydrosilylation of Phenylacetylene

Astle, Maxwell A.; Weilhard, Andreas; Rance, Graham A.; LeMercier, Tara M.; Stoppiello, Craig T.; Norman, Luke T.; Fernandes, Jesum Alves; Khlobystov, Andrei N.

Abstract

A method of pore fabrication in the walls of carbon nanotubes has been developed, leading to porous nanotubes that have been filled with catalysts and utilized in liquid- and gas-phase reactions. Chromium oxide nanoparticles have been utilized as highly effective etchants of carbon nanotube sidewalls. Tuning the thermal profile and loading of this nanoscale oxidant, both of which influence the localized oxidation of the carbon, have allowed the controlled formation of defects and holes with openings of 40–60 nm, penetrating through several layers of the graphitic carbon nanotube sidewall, resulting in templated nanopore propagation. The porous carbon nanotubes have been demonstrated as catalytic nanoreactors, effectively stabilizing catalytic nanoparticles against agglomeration and modulating the reaction environment around active centers. CO2 sorption on ruthenium nanoparticles (RuNPs) inside nanoreactors led to distinctive surface-bound intermediates (such as carbonate species), compared to RuNPs on amorphous carbon. Introducing pores in nanoreactors modulates the strength of absorption of these intermediates, as they bond more strongly on RuNPs in porous nanoreactors as compared to the nanoreactors without pores. In the liquid-phase hydrosilylation of phenylacetylene, the confinement of Rh4(CO)12 catalyst centers within the porous nanoreactors changes the distribution of the products relative to those observed in the absence of the additional pores. These changes have been attributed to the enhanced local concentration of phenylacetylene and the environment in which the catalytic centers reside within the porous carbon host.

Citation

Astle, M. A., Weilhard, A., Rance, G. A., LeMercier, T. M., Stoppiello, C. T., Norman, L. T., …Khlobystov, A. N. (2022). Defect Etching in Carbon Nanotube Walls for Porous Carbon Nanoreactors: Implications for CO2 Sorption and the Hydrosilylation of Phenylacetylene. ACS Applied Nano Materials, 5(2), 2075-2086. https://doi.org/10.1021/acsanm.1c03803

• Journal Article Type: Article
• Acceptance Date: Jan 21, 2022
• Online Publication Date: Feb 7, 2022
• Publication Date: Feb 25, 2022
• Deposit Date: Mar 18, 2022
• Publicly Available Date: Feb 8, 2023
• Journal: ACS Applied Nano Materials
• Print ISSN: 2574-0970
• Electronic ISSN: 2574-0970
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 5
• Issue: 2
• Pages: 2075-2086
• DOI: https://doi.org/10.1021/acsanm.1c03803
• Public URL: https://nottingham-repository.worktribe.com/output/7418333
• Publisher URL: https://pubs.acs.org/doi/10.1021/acsanm.1c03803
• Additional Information: This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Nano Material,copyright© American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acsanm.1c03803