Inkjet Printing Transparent and Conductive MXene (Ti₃C₂T_x) Films: A Strategy for Flexible Energy Storage Devices

Abstract

MXene is a generic name for a large family of two-dimensional transition metal carbides or nitrides, which show great promise in the field of transparent supercapacitors. However, the manufacturing of supercapacitor electrodes with a high charge storage capacity and desirable transmittance is a challenging task. Herein, a low-cost, large-scale, and rapid preparation of flexible and transparent MXene films via inkjet printing is reported. The MXene films realized the sheet resistance (R s) of 1.66 ± 0.16 MΩ sq–1 to 1.47 ± 0.1 kΩ sq–1 at the transmissivity of 87–24% (λ = 550 nm), respectively, corresponding to the figure of merit (the ratio of electronic to optical conductivity, σDC/σOP) of ∼0.0012 to 0.13. Furthermore, the potential of inkjet-printed transparent MXene films in transparent supercapacitors was assessed by electrochemical characterization. The MXene film, with a transmittance of 24%, exhibited a superior areal capacitance of 887.5 μF cm–2 and retained 85% of the initial capacitance after 10,000 charge/discharge cycles at the scan rate of 10 mV s–1. Interestingly, the areal capacitance (192 μF cm–2) of an assembled symmetric MXene transparent supercapacitor, with a high transmittance of 73%, still surpasses the performance of previously reported graphene and single-walled carbon nanotube (SWCNT)-based transparent electrodes. The convenient manufacturing and superior electrochemical performance of inkjet-printed flexible and transparent MXene films widen the application horizon of this strategy for flexible energy storage devices.

Inkjet-Printed Silver Nanowire Ink for Flexible Transparent Conductive Film Applications

“…In recent years, printed electronics (PE) have been considered as an alternative to conventional silicon-based technology due to high manufacturing speed, large-area, low cost, environmental friendliness, and particularly applicable to flexible functional devices [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. PE refers to the electronic product manufacturing technology that functional conductive inks are directly deposited onto substrate to form electronic component or circuit by printed process.…”

“…PE refers to the electronic product manufacturing technology that functional conductive inks are directly deposited onto substrate to form electronic component or circuit by printed process. Common industrial PE process includes screen printing [ 6 ], gravure printing [ 7 ], roll to roll printing [ 8 ], inkjet printing [ 10 ], and so on [ 11 , 12 , 13 , 14 ], and have been applied in some fields such as organic electronics [ 5 , 6 ], flexible electronics [ 2 , 3 , 4 , 11 ], wearable electronics [ 12 ], etc. Among those, inkjet printings particularly attractive in making controllable structure patterned circuits since it offers digital control on the printing process, is easy to integrate into a high throughput, and can be printed for better functional outcome [ 13 , 14 , 15 ].…”

A Simple Approach to MXene Micropatterning from Molecularly Driven Assembly

“…Among thin films with a thickness of around 5–250 nm, the current proposed molecularly driven assembled patterning technique showed an impressively lower resistance than other patterns prepared by different techniques. In detail, the sheet resistance of the MDA MXene film (154.67 Ω/□) is almost 10 4 times lower than that of inkjet printing 43 (1.66 × 10 6 Ω/□). Similarly, it is also lower from 3 to 52 times than the sheet resistance of spray coating 39 (500–8000 Ω/□) and 15 times lower than that of magnetron sputtering deposition (2300 Ω/□) 42 published previously.…”

Two‐dimensional MXenes: New frontier of wearable and flexible electronics

“…[28][29][30][31][32][33][34] The enriched structural features of MXene enable the fabrication of devices from bioinspired sources 35,36 and their integration into textile or planar substrates for wearable electronics, 15,37,38 realizing various geometrics such as smart textile-based devices, printed electronic devices, and 3D-configured devices (e.g., aerogels and hydrogels) for functional applications. 24,[39][40][41][42] Moreover, the improved coupling and hybridization of MXene with other materials at the nanoscale makes it one of the most intriguing materials for wearable applications. 43 The next few years are expected to witness tremendous progress in efficiently producing and handling MXene-based nanoelectronic materials.…”

“…Specifically, higher electrical conductivity and tunable surface functional groups have enabled MXenes to be used in several electronic systems, for instance, in advanced healthcare systems, 2,24 flexible electronics, 25–27 and wearable energy‐related fields 28–34 . The enriched structural features of MXene enable the fabrication of devices from bioinspired sources 35,36 and their integration into textile or planar substrates for wearable electronics, 15,37,38 realizing various geometrics such as smart textile‐based devices, printed electronic devices, and 3D‐configured devices (e.g., aerogels and hydrogels) for functional applications 24,39–42 . Moreover, the improved coupling and hybridization of MXene with other materials at the nanoscale makes it one of the most intriguing materials for wearable applications 43 .…”