Inkjet‐Printed High‐Performance Flexible Micro‐Supercapacitors with Porous Nanofiber‐Like Electrode Structures

Flexible planar micro‐supercapacitors (MSCs) with unique loose and porous nanofiber‐like electrode structures are fabricated by combining electrochemical deposition with inkjet printing. Benefiting from the resulting porous nanofiber‐like structures, the areal capacitance of the inkjet‐printed flexible planar MSCs is obviously enhanced to 46.6 mF cm^?2, which is among the highest values ever reported for MSCs. The complicated fabrication process is successfully averted as compared with previously reported best‐performing planar MSCs. Besides excellent electrochemical performance, the resultant MSCs also show superior mechanical flexibility. The as‐fabricated MSCs can be highly bent to 180° 1000 times with the capacitance retention still up to 86.8%. Intriguingly, because of the remarkable patterning capability of inkjet printing, various modular MSCs in serial and in parallel can be directly and facilely inkjet‐printed without using external metal interconnects and tedious procedures. As a consequence, the electrochemical performance can be largely enhanced to better meet the demands of practical applications. Additionally, flexible serial MSCs with exquisite and aesthetic patterns are also inkjet‐printed, showing great potential in fashionable wearable electronics. The results suggest a feasible strategy for the facile and cost‐effective fabrication of high‐performance flexible MSCs via inkjet printing.     

Fabrication of a 3D Nanoscale Crossbar Circuit by Nanotransfer‐Printing Lithography

Nanotransfer‐printing lithography simplifies the fabrication of a 3D nanoscale crossbar circuit. Gold nanowires 100 nm in width and with 100 nm spacing are printed onto a polymer layer of electrically switchable, LiClO₄‐doped poly[2‐methoxy‐5‐(2′‐ethylhexyloxy)‐p‐phenylene vinylene] mixed with an epoxy. The transfer process can be repeated to obtain a multilayer nanoscale crossbar structure. This process paves the way toward fabricating 3D circuits with ultrahigh device density and neuromorphic architectures.