Improving the Antioxidant Properties of Tin-Based Perovskite for the Enhanced Performance of Near-Infrared Light-Emitting Diodes Through the Synergy of Sn and SnF2

Tin-based perovskite has emerged as an excellent luminescent material due to its non-toxicity and narrow bandgap compared to lead-based perovskite. However, its tin ions are easily oxidized by oxygen, which leads to increased vacancy defects and poor crystallinity, presenting a significant challenge in obtaining high-quality perovskite films. In this context, we introduced an approach by synergistically adding SnF₂ and tin powder into the precursor solution to enhance the antioxidation of Sn ions. This method effectively improved the crystallinity of the perovskite films, reduced the density of defect states, and enhanced the photoluminescence performance of the films. Based on these findings, we successfully fabricated tin-based near-infrared perovskite light-emitting diodes (PeLEDs). With a 20% improvement in the Sn²⁺ content in the film, we achieved a threefold increase in the external quantum efficiency of the devices, reaching 3.6%.