Self-powered Sb₂S₃ photodetectors with efficient carrier transport enabled by compact vertical TiO₂ nanorods

Antimony sulfide (Sb₂S₃) photodetectors (PDs) possess extensive application prospects. Efficient carrier transport of a PD significantly affects the detectivity and response speed. Herein, we propose an all-inorganic self-powered Sb₂S₃ PD based on vertical TiO₂ nanorods (NRs). The spray-coated 15-nm TiO₂ thin film as a seed layer ensures the growth of compact vertical TiO₂ nanorod arrays by the hydrothermal method. One-dimensional TiO₂ nanorods facilitate photocarrier separation and transport to enhance device performance. Ultimately, the Sb₂S₃ PD achieves a responsivity of 0.29 A/W, a specific detectivity of 3.37 × 10¹² Jones, and a response time of 7.8 µs, showing great potential in commercial applications.