Asymmetric MXene–Cellulose Nanofiber Membranes Fabricated via Laser Etching for Planar Iontronic Devices

Artificial nanochannels exhibiting rectification functions are highly promising for applications in the field of iontronics. Introducing asymmetric elements into nanochannels to achieve easy-to-integrate planar ion diodes remains a challenge. Herein, the fabrication of planar asymmetric ion diodes is reported through laser etching at the tips of triangular MXene-cellulose nanofiber (CNF) hybrid membranes. The ion rectification performance is systematically optimized by varying membrane dimensions and laser etching parameters, culminating in a high ion rectification ratio of 33.2. Building on this achievement, it demonstrates their utility in iontronic devices. An ion rectifier bridge, fabricated by integrating four such ion diodes, successfully converted alternating current (AC) signals. This research provides a straightforward and feasible approach to manufacturing planar ion diodes and underscores their significant potential for application in ion-based circuits.