| 초록 |
Lead (Pb)- based perovskite solar cells (PSCs) with efficiency over 25% and high stability have been reported, however, Pb-free PSCs should be developed for the commercialization of PSCs due to the toxicity of Pb. Among the candidates to replace Pb, tin (Sn)-based PSCs are promising for their low band gap and high carrier. However, it is still a serious challenge to obtain high efficiency and stability for tin-based PSCs due to the facile oxidation of Sn2+. Here, we proposed a simple Cl--doping method to increase the resistance to oxidation of Sn2+. in Sn-based PSCs. Cl--doped perovskite film had larger grain sizes and highly oriented crystals, which increased the carrier mobility and reduced the trap states of the perovskite film. In addition, we revealed that Cl- located at the surface defects, and thereby prevented the oxidation of Sn2+. As a result, the highest efficiency of 7.14% was achieved with high reproducibility and stability under ambient conditions. |
