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Bis (8-hydroxyquinoline) copper (CuQ2) is an important organometallic complex based on a central metal cation coordinated to quinolate ligands. However, CuQ2 exhibits limitations such as low fluorescence intensity, short fluorescence lifetime, and low efficiency of visible light absorption. In this study, density functional theory (DFT) calculations were performed to investigate the frontier molecular orbitals of CuQ2, revealing its potential for excellent luminescence properties. Subsequently, CuQ2 was synthesized using physical vapor deposition (PVD), yielding micron-sized CuQ2 particles. CuQ2 micron particles were characterized using scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD), fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), ultraviolet visible spectroscopy (UV–Vis), photoluminescence and fluorescence lifetime. The results demonstrate that the deposition temperature significantly influences the morphology, thermal stability and fluorescence properties of CuQ2. At a deposition temperature of 200 °C, the CuQ2-C sample forms spherical micron particles with uniform morphology, enhanced thermal stability, optimal visible light absorption efficiency, and highest fluorescence intensity. The CuQ2-C sample exhibits a maximum emission wavelength of 660 nm, a maximum excitation wavelength of 333 nm, and a fluorescence lifetime of 10.646 μs. [ABSTRACT FROM AUTHOR]

Bis(8‐hydroxyquinolates) Zinc (Znq2) can be used as a light‐emitting layer material in OLED devices to achieve its efficient electroluminescence effect. In this paper, Znq2 powder has been successfully synthesized and modified by the physical vapor deposition (PVD) method. Precursors and nano‐materials are characterized by XRD, SEM, PL, and so on. The performance of the modified material has been significantly improved. The emission intensity and absorption intensity in the deposited products increased with the increase in PVD temperature. At 453 K, luminous properties such as luminous intensity reach the optimal value including its fluorescence lifetime. Fluorescence lifetime values vary from 13 to 17 ns with the increase in temperature. The luminescence mechanism is also discussed. The energy gap and absorption spectrum of HOM‐LUMO are calculated by the DFT/UB3LYP method. The experimental values agree well with the theoretical values. The nanomaterial crystals modified by PVD technology are more orderly, impurities are reduced, and the luminous stability of the material is improved, which may be one of the reasons for the relatively slow decline in product life. The research combined with theoretical simulation is expected to be helpful to the research and promotion of such materials. [ABSTRACT FROM AUTHOR]