Correction to: Nature Reviews Materials https://doi.org/10.1038/s41578-023-00611-8, published online 23 November 2023.

In the version of the article initially published, in the second paragraph of the “Database definition of CNTs” section, the phrase now reading “additional information about CAS Registry Numbers can be found at https://www.cas.org/cas-data/cas-registry” originally read “the full list of CAS registry numbers is available at SciFinder.com”. This has now been amended in the HTML and PDF versions of the article.