Two-dimensional lamellar MXene/three-dimensional network bacterial nanocellulose nanofiber composite Janus membranes as nanofluidic osmotic power generators

In the field of nanofluidic osmotic power generators, it has been an ultimate but seemingly distant goal to controllably fabricate the different-dimensional confined space including slits, network, nanochannels or their composition to control the ion transport. We demonstrated ion transport behaviors through ultimately 2D lamellar MXene/3D network bacterial nanocellulose nanofiber composite Janus membranes under the different transmembrane concentration gradient. The heterogeneous multilayers Janus membrane comprised effectively stacked hydrophobic MXene to hydrophilic bacterial nanocellulose (BNC). The asymmetric cations transport phenomena were explained in terms of asymmetric surface charges polarization in the confined space. Our re-sults provided a facile and general strategy for studying the effects of membrane-scale confinement, which was important for the development of biomimetic energy conversion, ionic seizing, chemical sensing and other nanoscale technologies.