Plasmonic nanoprism enhanced quasi 2D Ruddlesden Popper layered perovskite photodetectors
Compared with the three dimensional (3D) hybrid perovskite materials, the Ruddlesden Popper layered two dimensional (2D) perovskites are much more stable due to the introduction of large hydrophobic cations. And they have many important applications in optoelectronic devices. Here, we demonstrate that the performance of the quasi two dimensional (quasi 2D) perovskite photodetectors (PDs) can be improved by incorporating a layer of SiO2 coated AuAg alloyed nanoprisms (AuAg NPrisms@SiO2) Incorporation of AuAg NPrisms@SiO2 can increase the external quantum efficiency (EQE) values of the device over a broadband wavelength range. Under 532 nm laser illumination at an incident power density of 1 x 10 4 mW cm 2, the quasi 2D perovskite based PD with AuAg NPrisms@SiO2 exhibits a high EQE of 1670% at a low driving voltage of 0.3 V. Responsivity (R) and detectivity (D* reach 7.15 A W 1 and 3.2 x 1013 Jones, increased by 51.2% and 68.4% with respect to the control PD. Studies show that AuAg NPrisms@SiO2 incorporation can help to form high quality crystalline quasi 2D perovskite films, increase light absorption in the active layer, accelerate exciton dissociation at the interface and facilitate charge transport in the devices. These synergistic effects contribute to the improvement of EQE, R, D* and stability of the device after AuAg NPrisms@SiO2 doping. This work contributes to the fabrication of low cost and high performance PDs.