High-detectivity Ni2+-doped CsPbI3 Nanorod UV Photodetectors

Growth of qualified single-crystalline perovskite nanorods. High-purity, high-crystallinity Ni 2+ -doped CsPbI 3 nanorods are successfully prepared by introducing ion doping. • The substantially enhanced stability. The introduction of Ni 2+ doping improved the stability of the nanorods, allowing the Ni 2+ -doped CsPbI 3 nanorods to maintain their structural and optical integrity for more than 5 weeks under ambient conditions. • The overall excellent performance of the as-constructed PDs. The introduction of Ni 2+ doping reduced the defect concentration and carrier recombination rate. The detectivity of the photodetectors is comparable to the best-reported values among both undoped and ion-doped one-dimensional CsPbI 3 nanomaterial-based photodetectors (The Ni 2+ -doped CsPbI 3 nanorod PD has a responsivity of 1.08 × 10 3   A/W, a detectivity of 1.11 × 10 14 Jones, and an external quantum efficiency of 3.58 × 10 5 %, respectively). CsPbI 3 nanomaterials have attracted significant attention in optoelectronic devices due to their high carrier mobility and long diffusion length. Among them, one-dimensional (1D) CsPbI 3 nanomaterials offer more direct charge-carrier transport channels, making them ideal candidates for constructing high-performance micro/nanoscale photodetectors (PDs). However, CsPbI 3 nanomaterials still exhibit a high defect density within the crystal structure, which exacerbates carrier recombination. In this work, we successfully prepared Ni 2+ -doped CsPbI 3 nanorods with high crystallinity via a hot-injection method by partially substituting Ni 2+ for Pb 2+ . The as-prepared nanorods remain stable under ambient conditions for over five weeks. Ni 2+ doping reduces the defect-state density and electron–hole recombination rate of the CsPbI 3 nanorods. Meanwhile, the induced electronically active states facilitate photoexcitation, thereby collectively enhancing the photoelectric performance of the CsPbI 3 nanorods. The ultraviolet (UV) PD assembled based on Ni 2+ -doped CsPbI 3 nanorods exhibits excellent overall performance, featuring a detectivity of up to 1.11 × 10 14 Jones, which is comparable to the reported detectivity values of high-performance 1D CsPbI 3 -based photodetectors measured under different experimental conditions. This work provides some guidance for the development of high-performance UV optoelectric devices. Download: Download high-res image (194KB) Download: Download full-size image High-quality Ni 2+ -doped CsPbI 3 nanorods are successfully synthesized. The UV photodetector exhibits outstanding photoelectric performance, achieving a responsivity of 1.08 × 10 3   A/W, a detectivity of 1.11 × 10 14 Jones, and an external quantum efficiency of 3.58 × 10 5 %.