2D MXene-Molecular Hybrid Additive for High-Performance Ambipolar Polymer Field-Effect Transistors and Logic Gates

MXenes are highly conductive layered materials that are attracting a great interest for high-performance opto-electronics, photonics, and energy applications.. Their non-covalent functionalization with ad hoc molecules enables the production of stable inks of 2D flakes to be processed in thin-films. Here, the formation of stable dispersions via the intercalation of Ti3C2Tx with didecyldimethyl ammonium bromide (DDAB) yielding Ti3C2Tx-DDAB, is demonstrated. Such functionalization modulates the properties of Ti3C2Tx, as evidenced by a 0.47 eV decrease of the work function. It is also shown that DDAB is a powerful n-dopant capable of enhancing electron mobility in conjugated polymers and 2D materials. When Ti3C2Tx-DDAB is blended with poly(diketopyrrolopyrrole-co-selenophene) [(PDPP-Se)], a simultaneous increase by 170% and 152% of the hole and electron field-effect mobilities, respectively, is observed, compared to the neat conjugated polymer, with values reaching 2.0 cm(2) V-1 s(-1). By exploiting the balanced ambipolar transport of the Ti3C2Tx-DDAB/PDPP-Se hybrid, complementary metal-oxide-semiconductor (CMOS) logic gates are fabricated that display well-centered trip points and good noise margin (64.6% for inverter). The results demonstrate that intercalant engineering represents an efficient strategy to tune the electronic properties of Ti3C2Tx yielding functionalized MXenes for polymer transistors with unprecedented performances and functions.

Automated summary

MXenes are highly conductive layered materials that can be functionalized to enhance electron mobility in conjugated polymers and 2D materials, resulting in unprecedented performance and functionality for polymer transistors. Intercalant engineering represents an efficient strategy to tune the electronic properties of MXenes, leading to the fabrication of high-performance opto-electronics and energy applications.