Surface plasmon enhanced ultrathin Cu2ZnSnS4/crystalline-Si tandem solar cells

Nanoscale Adv. 2023 Apr 12;5(11):2887-2896. doi: 10.1039/d2na00826b. eCollection 2023 May 30.

Abstract

Thin-film silicon solar cells have sparked a great deal of research interest because of their low material usage and cost-effective processing. Despite the potential benefits, thin-film silicon solar cells have low power-conversion efficiency, which limits their commercial usage and mass production. To solve this problem, we design an ultrathin dual junction tandem solar cell with Cu2ZnSnS4 (CZTS) and crystalline silicon (c-Si) as the main absorbing layer for the top and bottom cells, respectively, through optoelectronic simulation. To enhance light absorption in thin-film crystalline silicon, we use silver nanoparticles at the rear end of the bottom cell. We utilize amorphous Si with a c-Si heterojunction to boost the carrier collection efficiency. Computational analyses show that within 9 μm thin-film c-Si, we achieve 28.28% power conversion efficiency with a 220 nm top CZTS layer. These findings will help reduce the amount of Si (∼10 vs. ∼180 μm) in silicon-based solar cells while maintaining high power conversion efficiency.