Zero-dimensional (0D) copper-based metal halides have exhibited great potential as luminescent materials with structural tunability and impressive emission properties. Luminescence from highly ordered self-assembly of copper halides is typically characterized by high photoluminescence quantum efficiencies (PLQEs) and large Stokes shifts, which are the most attractive features for active optical waveguides. Here, we report a novel highly luminescent organic copper halide, (PTMA)3Cu3I6 (PTMA: phenyltrimethylammonium), in which individual face- and edge-sharing [Cu3I6]3– clusters are surrounded by PTMA+ organic molecules, forming a highly ordered 0D crystal structure at the molecular level. Upon photoexcitation, (PTMA)3Cu3I6 single crystals exhibit a broadband yellow emission with a high PLQE of up to 80.3%. Theoretical calculations revealed that the photogenerated electron–hole pairs in (PTMA)3Cu3I6 are spatially separated from each other, i.e., electrons are preferred to be localized in PTMA+ organic molecules, while holes are highly localized in the inorganic [Cu3I6]3– clusters; thus, the emission arises from the radiative recombination of ligand-to-metal charge transfer (LMCT). In addition, colloidal nanocrystals of (PTMA)3Cu3I6 were successfully prepared, which show similar luminescence properties with their single crystals. The high PLQE, negligible self-absorption as well as the highly ordered self-assembly of metal halide clusters make (PTMA)3Cu3I6 microplates promising materials for low-loss optical waveguides, exhibiting an optical loss coefficient of 0.0157 dB μm–1 and highly linear polarized luminescence with a polarization anisotropy of 1.78.

Broadband white‐light emissions from low‐dimensional organic metal halides have received great attention for applications in energy‐efficient lighting and displays. However, the simultaneous realization of excellent color rendering indexes (CRIs) and high photoluminescence quantum efficiencies (PLQEs) in single‐component white‐light emitters remains a great challenge. Here, a unique 0D organic copper iodide (TPA)CuI2 (TPA = tetrapropylammonium) is developed, in which the edge‐sharing double trigonal planar [Cu2I4]2− dimers are surrounded by the organic cations TPA+, forming core/shell structures at the molecular level. These organic copper iodide single crystals exhibit a dual‐band white‐light emission covering the entire visible spectrum with a high PLQE of 84.4% and an excellent CRI of 91.3. In addition, (TPA)CuI2 nanocrystals are successfully synthesized and exhibit optical properties similar to those of the single‐crystal counterparts. Detailed photophysical studies reveal that the dual‐band emission originates from two self‐trapped emitting states in [Cu2I4]2− dimers, whose populations are strongly dependent on the temperature. The promising applications of (TPA)CuI2 as efficient and high CRI phosphors are demonstrated by a white‐light light‐emitting diode with a Commission Internationale de l'Eclairage coordinate of (0.31, 0.33).

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C 60 : Li F nanocomposite thin films were synthesized by physical vapor coevaporation. It is found that the nano-composite films are extremely conductive even at high LiF concentrations of up to 75wt% and that the films form Ohmic contacts with Al electrodes. IR measurements showed evidence of charge transfer from LiF to C60. Scanning electron microscope studies showed that C60:LiF (75wt%) nanocomposite forms uniform films. Compared with an archetypical tris(8-hydroxyquinolinato)alumina based device, OLEDs with the C60:LiF composite electron transport materials have lower driving voltages and higher power efficiencies.

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