Robust stable MoS2/GO filtration membrane for effective removal of dyes and salts from water with enhanced permeability

Abstract

Robust stable filtration membranes based on graphene oxide (GO), with fast and efficient capacity to separate dyes or salts from water, are highly necessary to maintain fresh water resources, but still a challenge to achieve. Herein, an easy and effective route has been demonstrated to address this challenge by intercalating GO with molybdenum disulfide (MoS2) nanosheets. Prompted by the strong van der Waals interactions between GO and MoS2 and the weak interaction between MoS2 and H2O molecules, the interlayer stabilizing force within the MoS2/GO filtration membrane has been greatly enhanced. Therefore, robust stability against harsh conditions (pH values from 3 to 11) without any additional cross-linkers can be realized. Additionally, compared with pure GO membrane, our MoS2/GO membrane exhibits both enhanced pure water flux (from 8.83 L·m−2·h−1 to 48.27 L·m−2·h−1) and improved salts removal capacity (i.e., K3Fe(CN)6 (from 54.32% to 96.85%)), without deteriorating its dyes rejection ratio (i.e., methylene blue (more than 99.50%)). Meanwhile, the membrane also has outstanding cycling stability. For the ubiquitous van der Waals forces between two-dimensional materials, our method can be easily extended to construct other stable and highly efficient filtration membranes.