Abstract
Printable large-area electronics continue to attract increasing interest from the scientific and industrial communities, owing to their potential for cost-efficient manufacturing. However, the exerted efforts primarily focus on processing semiconductors and dielectrics, with relatively limited attention toward printable electrode materials. In this respect, the family of two-dimensional (2D) transition metal carbides/nitrides, so-called MXenes, have emerged as promising electrode materials owing to their metal-like conductivity and solution processability. Despite their advanta-geous characteristics, however, to date, the application of MXene electrodes in the area of printed electronics has been marginally explored. Herein, we develop all-solution-processable In2O3/ZnO heterojunction metal oxide thin-film transistors (TFTs) utilizing Ti3C2Tx MXene as the gate and the electron-injecting contacts, entirely spray-coated under ambient conditions. We show that the manufacturing of these fully spray-coated devices can be scaled-up to 4 in. substrates without compromising their operating characteristics. The fabricated TFTs exhibit electron mobility of 3 cm2 V-1 s-1 with an on/off ratio of >104. Our findings demonstrate the possibility of replacing conventional metal contacts with spray-coated MXene electrodes for application in large-area electronics.