An unprecedented high-temperature-tolerance 2D laminar MXene membrane for ultrafast hydrogen sieving

Abstract

Exploring high selectivity molecular sieving membranes and the corresponding facile assembly methods are extremely critical for the gas separation. In this work, we demonstrated a high-temperature-tolerance 2D membrane for hydrogen sieving. This membrane was prepared by a vacuum-assisted filtration with a subsequent drying process in which all the manipulations were based on the ambient conditions. The XRD study indicates that the crystal structure is quite stable even at a wide temperatures range from 25 to 500 °C. The interlayer spacing of MXene membrane was shrank from 3.4 Å (25 °C) to 2.7 Å (500 °C) after such high temperature treatment, reinforcing the molecular sieving properties. The membrane exhibited the moderate H2 permeation of 2.05 × 10−7 mol m−2 s−1 Pa−1 and good selectivity of 41 for H2/N2 mixture at 320 °C. Benefiting from the excellent chemical stability of MXene membranes, no degradation was found for permeation and separation test up to 200 h. The high separation performance and the exceptional high-temperature stability mirror the 2D MXene membranes as a promising candidate for the separation of industrial gas mixtures containing hydrogen.