Nanotube membrane refers to a thin layer of nanotubes that can selectively filter substances at a molecular or atomic level. There are several synonyms for nanotube membrane, such as nanoporous membrane, nanofilter, nanosieve, and nanomembrane. These terms emphasize the membrane's porous nature and its ability to filter tiny particles. Another synonym is a molecular sieve, which points to the membrane's ability to separate molecules based on their size and shape. Additionally, terms such as carbon nanotube (CNT) membrane or graphene nanotube (GNT) membrane specify the material used to construct the membrane, highlighting their unique properties and potential applications.