Inkjet‐Printed, Large‐Area, Flexible Photodetector Array Based on Electrochemical Exfoliated MoS2 Film for Photoimaging

Although a variety of MoS 2 ‐based photodetectors have been reported over the last few years, the controlled fabrication of large‐area photodetector array for photoimaging remains a major challenge due to the low yield and poor quality of MoS 2 film. Herein, a high‐performance inkjet‐printed flexible photodetector array based on stacked MoS 2 nanosheets is demonstrated for the first time. The 2H phase MoS 2 nanosheets is obtained by intercalating quaternary ammonium cation into MoS 2 bulk. The inkjet‐printed photodetector achieves excellent performance with a highest responsivity of 552.5 A W −1 , detectivity of 1.19 × 10 12 Jones, and fast response and recovery time of 23 and 26 ms, respectively, at room temperature. Furthermore, a photodetector array with 85 pixels per inch is successfully constructed, and the letter of “T” is clearly recognized. These results indicate that electrochemical exfoliation coupled with inkjet printing has great prospect for application in high‐performance photodetector array. Besides, the electrochemical exfoliation is also successfully applied to obtain the ink of In 2 Se 3 , black phosphorus (BP), and MoTe 2 . It is believed that this work paves the way for various potential printable optoelectronics based on 2D materials.