In the "Materials" branch, terms with an especially high growth rate (>1.5 fold increase in publications over 2020-2022) include poly(butylene adipate-co-terephthalate) (PBAT), ciprofloxacin, biochar, cellulose nanofibers, and MXene nanosheets. This branch includes both materials that are often used in combination with CNTs as well as materials that are detected or removed using CNTs.