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Title: Overcoming the Limitations of MXene Electrodes for Solution‐Processed Optoelectronic Devices

MXenes constitute a rapidly growing family of 2D materials that are promising for optoelectronic applications because of numerous attractive properties, including high electrical conductivity. However, the most widely used titanium carbide (Ti3C2Tx) MXene transparent conductive electrode exhibits insufficient environmental stability and work function (WF), which impede practical applications Ti3C2Txelectrodes in solution‐processed optoelectronics. Herein, Ti3C2TxMXene film with a compact structure and a perfluorosulfonic acid (PFSA) barrier layer is presented as a promising electrode for organic light‐emitting diodes (OLEDs). The electrode shows excellent environmental stability, highWFof 5.84 eV, and low sheet resistanceRSof 97.4 Ω sq−1. The compact Ti3C2Txstructure after thermal annealing resists intercalation of moisture and environmental contaminants. In addition, the PFSA surface modification passivates interflake defects and modulates theWF. Thus, changes in theWFandRSare negligible even after 22 days of exposure to ambient air. The Ti3C2TxMXene is applied for large‐area, 10 × 10 passive matrix flexible OLEDs on substrates measuring 6 × 6 cm. This work provides a simple but efficient strategy to overcome both the limited environmental stability and lowWFof MXene electrodes for solution‐processable optoelectronics.

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Award ID(s):
Author(s) / Creator(s):
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Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials
Medium: X
Sponsoring Org:
National Science Foundation
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