Covalent Aminopropyl Functionalization Tailors Ti3C2Tx MXene for High-Performance Flexible NIR Photodetectors

en This link goes to a English section zh This link goes to a Chinese section Ti 3 C 2 T x MXene, with its exceptional electrical conductivity, mechanical flexibility, and processability, compatible with wearable and integrated systems, plays a crucial role in advancing flexible photodetectors for intelligent perception systems and bioinspired artificial vision. However, its intrinsic narrow bandgap (< 0.1 eV) and the limited diversity of surface functionalization strategies severely constrain its use as a photosensitive layer in photodetectors. Herein, a surface engineering strategy is developed to covalently graft aminopropyl groups onto the surface of Ti 3 C 2 T x via Si-O-Ti linkages, thereby successfully widening its bandgap to 1.46 eV. The resulting Au/Ti 3 C 2 T x -NH 2 /Au flexible photodetector exhibits excellent bending resistance and demonstrates an ultrahigh on–off ratio of 10 12 under 808 nm laser excitation, along with an excellent responsivity of 3.72 × 10 4 A W −1 and high specific detectivity of 1.03 × 10 18 Jones. Additionally, the fabricated 147-pixel image sensor achieves high-contrast imaging of the “MAX” pattern, providing a new pathway for advancing high-performance flexible near-infrared photodetector technologies in bioinspired vision and flexible wearable image sensing. 摘要 en This link goes to a English section zh This link goes to a Chinese section 凭借其优异的导电性、机械柔韧性以及与可穿戴和集成系统兼容的加工性能,Ti 3 C 2 T x MXene在推动面向智能感知系统和仿生人工视觉的柔性光电探测器发展中发挥着重要作用。然而,其本征窄带隙(< 0.1 eV)以及表面功能化策略的多样性不足,严重限制了其作为光敏层在光电探测器中的应用。为此, 本文开发了一种表面工程策略,通过Si-O-Ti键将氨丙基共价接枝到Ti 3 C 2 T x 表面,成功将其带隙拓宽至1.46 eV。所制备的Au/Ti 3 C 2 T x -NH 2 /Au柔性光电探测器在808 nm激光激发下表现出优异的抗弯折性能、高达10 12 的超高开关比、3.72 × 10 4 A W −1 的出色响应度以及1.03 × 10 18 Jones的高比探测率。此外,所制造的147像素图像传感器实现了对“MAX”图案的高对比度成像,为在仿生视觉和柔性可穿戴图像传感领域推动高性能柔性近红外光电探测器技术的发展提供了新途径。