4 CONCLUSIONS
In conclusion, we successfully fabricated tubular MXene/SS membranes on commercial porous stainless steel substrates rapidly via electrophoretic deposition. Filamentous CNTs were used as fillers for macroporous substrates for the first time, which could effectively fill the big holes only on the substrate surface and modify the surface flatness without reducing the permeability of the substrate itself. After optimizing the electrophoresis process, the tubular MXene/SS2.5 membrane achieved excellent H2/CO2 separation performance. The corresponding H2/CO2 selectivity and hydrogen permeance were 55 and 1290 GPU, respectively, and the membrane showed outstanding long-term stability for up to 1250 h with good water vapor stability. Moreover, the repeatability of membrane preparation had also been adequately validated, where 93% of the membranes prepared in one batch exceeded the DOE target, showing great potential for industrial scale-up and practical application. Most importantly, this work proposed a method for the efficient preparation of 2D MXene nanosheet membranes on commercial tubular stainless steel substrates, which provided a valuable reference for the preparation of other types of 2D materials-based membranes. Furthermore, the work has also made specific contributions to the large-scale fabrication of 2D MXene membranes and the promotion of actual industrial applications.