Design of Biomimetic Leaf-type Hierarchical Nanostructure for Enhancing the Solar Energy Harvesting of Ultra-thin Perovskite Solar Cells
Huaxu Liang, Xinping Zhang, Bo Lin, Fuqiang Wang, Ziming Cheng, Xuhang Shi, Bachirou Guene Lougou
Abstract
Ultra-thin perovskite solar cells have the advantages of low cost, high efficiency and flexibility, and have significant potential applications. However, a severe optical loss is often observed in the ultra-thin perovskite solar cell due to the insufficient light absorption. In this study, inspired by the efficient light harvesting of hierarchical structure in leaf, the idea of biomimetic leaftype hierarchical nanostructure was introduced for designing highly efficient ultra-thin perovskite solar cells. In detail, three layers of hexagonal arrays of silica nanoparticles with different radius were used to construct the biomimetic leaf-type hierarchical structure. The biomimetic leaf-type hierarchical nanostructure was optimized by a finite-difference time-domain method combined with a particle swarm optimization algorithm to reduce the light reflection and increase the light absorption of the ultra-thin perovskite solar cells. The results indicated that the biomimetic leaf-type hierarchical nanostructure could enhance the light absorption of ultra-thin perovskite solar cells by maximum 39% at the long wavelength. The photocurrent of the perovskite solar cells with a biomimetic leaf-type hierarchical nanostructure was 8.4% higher than that of perovskite solar cells without a biomimetic leaf-type hierarchical nanostructure.