Efficient 3He/4He separation in a nanoporous graphenylene membrane

Helium-3 is a precious noble gas, which is essential in many advanced technologies such as cryogenics, isotope labeling and nuclear weapons. The current imbalance of He-3 demand and supply shortage leads to the search for an efficient membrane with high performance for He-3 separation. In this study, based on first-principles calculations, we demonstrated that highly efficient 3He harvesting can be achieved in a nanoporous graphenylene membrane with industrially-acceptable selectivity and permeance. The quantum tunneling effect leads to He-3 harvesting with high efficiency via kinetic sieving. Both the quantum tunneling effect and zero-point energy (ZPE) determine the He-3/He-4 separation via thermally-driven equilibrium sieving, where the ZPE effect dominates efficient He-3/He-4 separation between two reservoirs. The quantum effects revealed in this work suggest that the nanoporous graphenylene membrane is promising for efficient 3He harvesting that can be exploited for industrial applications.