Buried-Interface Kinetic Regulation of Crystallization Enables Efficient Near-Infrared Tin Perovskite LEDs

This is the authors' abstract. We don't add key points for this paper.

Near-infrared tin perovskite light-emitting diodes (PeLEDs) constitute a class of lead-free optoelectronic devices, but their performance suffers from rapid crystallization over a defective hole transport layer underneath the perovskite film. Here, we report a buried-interface kinetic regulation strategy for Cs-rich tin iodide perovskites. The buried interlayer regulated the initial growth of the perovskite film. This regulation delayed the emergence of emissive domains and promoted compact film growth without substantially perturbing the Sn-I framework. Spectroscopic and theoretical analyses reveal interfacial interactions with Sn-related sites, which help suppress defect formation and nonradiative losses. The optimized PeLEDs exhibited near-infrared electroluminescence centered at 945 nm and achieved a peak external quantum efficiency of 8.04%. This work highlights buried-interface kinetic regulation as an effective route toward efficient lead-free near-infrared tin perovskite LEDs.