Vertical SnS2/Cr–SnS2 n–n Homostructure for High-Responsivity and Fast-Response 405 nm Near-Ultraviolet Detectors

Near-ultraviolet (NUV) detectors based on two-dimensional (2D) materials have garnered considerable attention owing to their atomic-scale thickness, varied bandgap, and strong interaction with incident light. In this work, homostructures composed of tin disulfide/chromium–doped tin disulfide (SnS ₂ /Cr–SnS ₂ ) were proposed for 405 nm near-ultraviolet detectors. Afterward, superlative detectors were fabricated through the employment of micro-mechanical exfoliation and polydimethylsiloxane-assisted dry-transfer methods, anchored by the SnS ₂ Cr–SnS ₂ homostructures. The detectors demonstrated exceptional detection performance for 405 nm NUV radiation with a significant responsivity of $2.04\times 10^{{3}}\,\,\text {A}\cdot \text {W}^{-{1}}$ and a short response time of 8 ms, exceeding that of detectors based on most 2D materials and even commercial light detectors (Thorlabs FD11A–Si). The work presents an effective homostructure for high-performance SnS ₂ -based detectors, thereby opening an opportunity for the utilization of SnS ₂ in NUV detectors.