Recent progress on the smart membranes based on two-dimensional materials

Inspired by the biosystems, the artificial smart membrane to control the mass transport and molecular conversion has attracted increasing attention in the fields of membrane separation, desalination, nanofiltration, healthcare and environmental remediation. However, the trade-off limitations in polymeric membranes greatly hinder the development of smart membranes with high permeability and manipulability. Recently, inspired by the unique physical/chemical properties of two-dimensional (2D) materials, 2D materials-based smart membranes (2DSMs) with the ability of intelligent regulation under different stimuli are highly suitable for membrane applications. According to the desired properties, the 2DSMs with abundant functional groups can be designed through chemical modification to change the original properties and obtain tunable interlayer spacings under different external conditions. In this review, we summarize the recent progress on artificial smart membranes based on 2D materials. The design concept and fabrication strategy of 2DSMs are first introduced. Following that, the developed 2DSMs are introduced and classified by the type of responsive stimuli, including pH, magnetic field, electric field, light and temperature. Then, the 2DSMs exhibiting unique performances as membrane separation, pressure sensors, blue energy harvesting, photoelectrochemical sensors and biomimetic devices are presented. Finally, the perspectives and challenges in the developments of 2DSMs are discussed