Printable Zn₂GeO₄ Microwires Based Flexible Photodetectors with Tunable Photoresponses

Printed electronics have drawn considerable attention due to their unique features and broad applications in future portable and wearable electronic devices. Herein, a near-field direct-printing method is used to realize a precise manipulation of microwires in the level of the individual wire for depositioning in a desired position and direction. High-performance flexible photodetectors are fabricated on printed aligned Zn₂GeO₄ microwires arrays, which show excellent photoresponse, stability, and uniformity toward UV light irradiation. Studies find that the photocurrents can be easily tuned by adjusting the number of printed microwires, enabling a potential application in printable imaging sensors. Patterned flexible photodetector arrays are also fabricated with a high sensitivity (≈4 × 10³), precise manipulation, tunable photoresponses, and a good tolerance toward mechanical deformations. This work paves the way toward efficient fabrication of printable electronic device and facilitates their practical applications in future printed electronics, such as flexible and wearable functional devices, electronic textiles, transistors, and circuits.