Tailoring the separation performance of a carbon nanotube-based mixed matrix membrane decorated with metal–organic framework

A novel MOF–CNT composite was synthesized and applied to the preparation of MMM. Synthesized MMM of Cu-MOF-en@MWCNT MMM not only possess selective adsorption of dyes but also exhibit selective photodegradation of dyes. [Display omitted] •A Cu-MOF prepared by adding CH3COO– has smaller size and larger productivity.•The 1,4-H2NDC guest molecules reside in the cages of the Cu-MOF.•An amine-functionalized Cu-MOF has been successfully prepared by grafting method.•A novel filler of MMM derived from Cu-MOF-en and MWCNT-COOH.•The MMM can be served as a selective sorbent and photocatalyst. Synthesis of mixed matrix membranes (MMM) using carbon nanotubes (CNTs) has shown great prospects for achieving excellent selective separation because of its special structure. Nevertheless, the preparation of highly selective MMM faces challenges, which is attributed to the obstacles encountered by CNTs dispersion in polymer matrix and elimination of interface defects. A novel CNT-based composite decorated with metal–organic framework (MOF) was synthesized and applied to the preparation of MMM. MOF was post modified, and then carboxyl groups were inserted on the outer surface of CNTs. The synthetic MMM (Cu-MOF-en@MWCNT) not only has selective adsorption on dyes, but also has selective photodegradation on dyes. The method of using CNTs to wrap the outside of MOF has great potential in dye separation. The performance of MMM was further improved by decorating MOF on the filler to improve the selectivity to the designated dye.