Perovskite Capped ZnO Nanorods Ultraviolet/Visible Broadband Photodetectors

A high-performance broadband photodetector (PD) based on triple-cation perovskite (PVSK)/ZnO nanorods (ZnO NRs) is fabricated. Multiple material analysis, including scanning electron microscope (SEM), absorption spectrum, X-ray diffractometer (XRD), and high-resolution transmission electron microscopy (HR-TEM) are conducted. The analyses indicate that a dense perovskite film is closely capped on the ZnO NRs. A light source with different wavelength is applied to evaluate the photosensitive behaviors along with impulse responses of the PVSK/ZnO NRs PDs and pure ZnO NRs PDs. Results show that the PVSK/ZnO NRs PDs are sensitive to the ultraviolet (UV) and visible light, while the pure ZnO NRs PDs are only sensitive to the UV light. Moreover, owing to the superior photoelectric properties of triple-cation perovskite than the mono-cation perovskite, the triple-cation PVSK/ZnO NRs PDs deliver a high declivity of 7.69
$ \,\times\, {10}^{12}$
, 1.49
$ \,\times\, {10}^{13}$
and 3.61
$ \,\times\, {10}^{13}$
Jones under the light illumination with a wavelength of 350, 450 and 600 nm, respectively. Triple-cation PVSK/ZnO NRs composites are promising materials for broadband wavelength detection from UV to visible light with high detectivity.