High‐Entropy Lead‐Free Organic–Inorganic Hybrid Perovskites Exhibiting Broad Absorption and Bright Golden Emission for LEDs

Metal halide perovskite nanomaterials are attractive for optoelectronic applications due to their exceptional optoelectronic properties; however, lead toxicity and stability issues significantly limit their practical use. High-entropy materials (HEMs) leverage multi-principal component synergy to form configurational entropy-stabilized solid solutions, exhibiting unique physicochemical properties and superior stability arising from atomic-scale chemical disorder and reconstructed local electronic states. Nevertheless, their luminescence efficiency often requires improvement. Here, we report the room-temperature synthesis of a novel organic-inorganic hybrid high-entropy perovskite, (TEA)₂(Zr_0.18Te_0.22Hf_0.2Sn_0.3Pt_0.1)Cl₆ (TEA = tetraethylammonium). Exploiting the synergistic effects among five diverse B-site cations, this material exhibits broad-spectrum-excitable broadband emission, producing a distinct golden light. The study demonstrates that this material retains 80% of its initial photoluminescence intensity after 1 h of continuous ultraviolet irradiation and maintains 60% of its original emission intensity even when heated to 340 K. Furthermore, its facile room-temperature synthesis facilitates promising applications, such as in light-emitting diodes and x-ray detection. These findings provide crucial insights for advancing the development of efficient and stable novel optoelectronic materials.