Flexible Transparent Near-Infrared Photodetector Based on 2D Ti₃C₂ MXene-Te Van Der Waals Heterostructures^†

Ti₃C₂ MXene serving as superior electrical conductors presents more specific performance such as transparency, conductivity than gold (Au), and even could form a heterostructure with active materials of the functional devices. Here, a Ti₃C₂ MXene-Te microplate van der Waals heterostructure based transparent near-infrared photodetector (PD) is exploited. Compared with Au-Te PD, the on-off ratio of the Ti₃C₂-Te PD is improved by seven orders of magnitude and reaches 9.51 × 10⁷ under 1064 nm laser illuminations. Benefiting from the utilization of flexible PET substrate and Ti₃C₂ conductors in manufacturing PD devices, the Ti₃C₂-Te PD exhibits excellent flexibility with no noticeable response change after being bent for different states and times. Moreover, 63% transmittance of the fabricated PD devices over the 500—1000 nm wavelength range is obtained. All the above results demonstrate the tremendous potential in wearable optoelectronics.