An ionic diode based on a spontaneously formed polypyrrole-modified graphene oxide membrane.

Asymmetric membranes derived from the stacking of graphene oxide (GO) nanosheets have attracted great attention for the fabrication of ionic diodes. Herein, we described an ionic diode based on a polypyrrole-modified GO membrane with a vertical asymmetry, which was achieved by a spontaneous oxidation polymerization of pyrrole monomers on one side of the GO membrane in vapor phase. This asymmetric modification resulted in an asymmetric geometry due to the occupation of the interlayer space of one side of the GO membrane by polypyrrole.

Rod-Cell-Mimetic Photochromic Layered Ion Channels with Multiple Switchable States for Controllable Ion Transport.

The controllable ion transport in the photoreceptors of rod cells is essentially important for the light detection and information transduction in visual systems. Herein, inspired by the photochromism-regulated ion transport in rod cells with stacking structure, layered ion channels have been developed with a visual photochromic function induced by the alternate irradiation with visible and UV light. The layered structure is formed by stacking spiropyran-modified montmorillonite 2D nanosheets on the surface of an alumina nanoporous membrane.