Space-Confined Growth of 2D Ultrathin Ternary CdZnTe Flakes toward High-Performance Photodetectors

Two-dimensional (2D) CdZnTe has been highly anticipated in high-performance photodetectors because of its excellent optoelectronic properties and the quantum confinement effect in 2D scale. However, due to the intrinsically nonlayered structure, the current obtained 2D CdZnTe structures are only applicable to amorphous or polycrystalline films with degraded properties, seriously limiting the exploration of its inherent characteristics and further application in optoelectronics. Here, we report, for the first time, the controllable growth of ultrathin 2D CdZnTe flakes (down to 3.2 nm) via space-confined chemical vapor deposition and demonstrate that the CdZnTe flakes are highly crystalline and possess high stability. The single-crystalline 2D CdZnTe flakes-based photodetectors exhibit outstanding broadband response varying from visible to near-infrared region, high responsivity of 80.6 A W-1 and specific detectivity of 1.86 × 1010 Jones under 405 nm illumination. Our study will open new territory for 2D ternary nonlayered materials in optoelectronic applications.