Zero‐Dimensional Organic–Inorganic Hybrid Zinc Halides for Multiple Applications in Anti‐Counterfeiting, X‐Ray Imaging and White LEDs

Abstract Zinc halides have been less explored even though they are a promising lead‐free family with the merits of environmental friendliness and low cost. Here, the organic–inorganic hybrid zinc halides are screened with aromatic molecules containing amino groups (MXDA: m‐Xylylenediamine, ABI: 2‐Aminobenzimidazole, pipda: 2‐piperidylmethylamine, p‐MPEA: p‐Methylphenethylamine), and six new compounds are discovered: (MXDA)ZnCl 4 ( 1 ), (ABI) 2 ZnCl 4 ( 2 ), (pipda) 2 H 2 OZnCl 2 ( 3 ), [(pipda) 4 Zn 2 Br 4 ]·H 2 O ( 4 ), (p‐MPEA) 2 ZnCl 4 ( 5 ), and (p‐MPEA) 2 ZnBr 4 ( 6 ). The discovered compounds exhibit diverse efficient light emissions (blue, green, yellow, and ultraviolet) under ultraviolet light irradiation. By doping Sb and Mn at the Zn site, (MXDA)ZnCl 4 exhibits different colors of light under excitation light of different wavelengths, so it is successfully used for anti‐counterfeiting. (MXDA)Zn 0.91 Mn 0.09 Cl 4 is also found to be an efficient X‐ray scintillator for X‐ray imaging. Among the as‐explored new phases, a maximum photoluminescent quantum yield of 82.60% is realized, enabling the utilization for white light‐emitting diodes. The results suggest that the zinc halides are a new lead‐free family with superior optoelectronic properties, which can be used for multiple applications.