This article demonstrates a significant broadband enhancement of light absorption and improvement of photon-generated-charge transfer in CH3NH3PbI3 perovskite solar cells by incorporating plasmonic Au–Ag alloy popcorn-shaped nanoparticles (NPs). Compared to conventional nanoparticles and nanorods, these popcorn-shaped NPs have many fine structures. The device's maximum power conversion efficiency (PCE) increases from 8.9% to 10.3%, namely 15.7% enhancement, with the aid of plasmonic popcorn-shaped NPs.
