Arrays of spherical nanostructured oxide particles for photon management enhancement in photovoltaic devices

Abstract

To better optimize the optical–electrical performance of photovoltaic devices, high-quality photon management and superior optical design should be developed. Herein, based on hot-spot materials of CsPbI₃ perovskite (PVK), the photon management strategy of integrated cheap spherical nanostructured oxide particles (SNOPs) enhanced photocurrent is developed and reported. Three SNOPs (SiO₂, ZrO₂, Al2O₃) with different refractive indices were integrated into different functional layers of CsPbI₃ perovskite solar cells (PSCs) to enhance the light-capture performance. Compared with reference PSCs, the short-circuit current density (J_SC) and power conversion efficiency (PCE) of the optimized device reached 20.96 mA cm⁻² (20.34 mA cm⁻²) and 18.55% (17.70%) without sacrificing electrical properties. Further experimental characterization demonstrated that improved performance originated from enhanced visible-light photon utilization, and the competitive mechanism between optical–electrical properties obtains effective mitigation. Moreover, this device with integrated SNOPs was optically numerically simulated and quickly predicted, verified with experimental results, and both showed good agreement. It proves that: (1) photocurrent enhancement mainly lies in the enhanced local optical field of the PVK layer due to specific interference design; (2) photon collection in different depths of the photogenerated electron layer becomes more regular and uniform so that efficiency increases slightly. Importantly, it provides viable insight into potential mechanisms of optical management.