Graphdiyne (GDY) is a new type of two-dimensional carbon allotrope. It is a new all-carbon nanostructured material after fullerenes, carbon nanotubes and graphene. In 2010, Li Yuliang, Academician Group For the first time, a high-quality graphene film was successfully synthesized on the surface of Cu foil by the cross-coupling reaction of hexamethylene benzene precursor. Graphene has a rich carbon chemical bond, a large conjugated system, wide interplanar spacing, and excellent chemical stability. It is known as the most stable allotrope of synthetic diacetylene. Its unique sp-sp2 carbon atoms, uniform pores and high π-conjugated structure have shown broad application prospects in gas separation, catalysis, water treatment, humidity sensors and energy.

The synthesis of Graphdiyne was reported as a 1 mm film on a copper surface. Graphdiyne was predicted to exhibit a nanoweb-like structure, characterized by triangular and regularly distributed pores, thus forming a nanoporous membrane. Due to the effective size of its pores, which almost matches the van der Waals radius of the helium atom, graphdiyne could behave as an ideal two-dimensional membrane for helium chemical and isotopic separation. The application of a graphdiyne based membrane as an efficient two-dimensional sieve for water filtration and purification technologies has been proposed.