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Exploiting the chirality transfer and amplification in the hierarchical chiral systems by the visible and accurate structures is still a challenge. Herein, a pair of homochiral metal‐organic frameworks (MOFs) DCF‐12 and LCF‐12 with high rigidity and high porosity are synthesized via reticular chemistry. Interestingly, these two enantiomers can act as nano‐containers, in which four chromophores, covering acridine, pyrene, 9,10‐Bis(phenylvinyl) anthracene (BPEA), and coronene can be introduced by in situ encapsulation. Importantly, the precise single crystal structures of all guest‐loaded MOFs by X‐ray diffraction technique can be obtained smoothly. It not only clearly reveals the chirality transfer from chiral host framework to achiral guest emitters through space chirality transfer, but also circularly polarized luminescence can be achieved and modulated through the synergistic effect. Extraordinarily, both pyrene@DCF‐12 and pyrene@LCF‐12 exhibit fascinating multi‐color tunable room temperature phosphorescence (RTP) and dynamic circularly polarized luminescence. Besides, the RTP quantum yields of pyrene@DCF‐12 and pyrene@LCD‐12 are high up to 75.39% and 73.43%, which exceeds most of that of RTP materials. These results demonstrate that chiral MOFs can serve as an accurate platform to investigate the mechanism of chirality transfer and amplification and to prompt the development of CPL‐active materials. [ABSTRACT FROM AUTHOR]

A single-component Ca 7 Mg 2 (PO 4) 6 :Dy3+, Eu3+ white-emitting phosphor was synthesized by a sol-gel approach. The effects of the amounts of Dy3+ ions and Eu3+ ions on the luminescence characteristics and crystal structure of Ca 7 Mg 2 (PO 4) 6 :Dy3+, Eu3+ were systematically investigated. The Ca 7 Mg 2 (PO 4) 6 :Dy3+, Eu3+ phosphors had a Ca 7 Mg 2 (PO 4) 6 structure with an R3c (161) space group. The Ca 7 Mg 2 (PO 4) 6 :Dy3+ phosphor showed emission peaks at both 484 nm (blue) and 576 nm (yellow), which led to the realization of white light. Furthermore, after codoping Eu3+ ions into the structure, a red emission peak (∼617 nm) appeared in the spectrum as a supplementary red component. A warm white light with a low correlated colour temperature (CCT) is obtained from Dy3+/Eu3+-codoped Ca 7 Mg 2 (PO 4) 6. The luminescence intensity at 483 K still reaches more than 73 % of that at 303 K. The packaged LEDs display a bright warm white light with CCT value and colour rendering index (CRI) of 3878 K and 86.7, respectively, which is comfortable for the human eye. With excellent luminescence performances, the white-emitting Ca 7 Mg 2 (PO 4) 6 :Dy3+, Eu3+ phosphor had a significant application potential in the w -LED field. [ABSTRACT FROM AUTHOR]

Silicon based erbium doped Ga 2 O 3 films and devices are fabricated. It is found that the intensity of Er3+ ions emission can be enhanced by optimizing the content of sensitizer as well as increasing the optical activity of Er3+ ions in the way of adjusting the annealing process. The indirectly excited luminescence of Er3+ ions can be improved, as measured by photoluminescence and electroluminescence, via selecting N 2 as the ambient, decreasing the annealing temperature or prolonging the thermal treatment time. Herein, light emitting devices present the maximum optical power density of ∼0.84 μW/cm2. This work proposes a way to optimize the indirect emission by regulating the content of sensitizers and the optical activity of Er3+ ions, beneficial to the practical use of electrically-driven silicon-based light sources. • Er doped Ga 2 O 3 heterojunction luminous films and devices are fabricated. • Emission intensity is linked with oxygen vacancies and the optical activity of Er3+. • Oxygen vacancies can be maintained by annealing heterostructures in nitrogen. • Optical activity of Er3+ can be enhanced by reducing the annealing temperature. • The heterostructure devices present the lowest working voltage of 10 V. [ABSTRACT FROM AUTHOR]

1.54 μm photoluminescence and electroluminescence are achieved from erbium doped Ga 2 O 3 films on silicon substrates and corresponding devices fabricated by sputtering, respectively. Efficient energy transfer between Ga 2 O 3 and erbium ions is realized in optical pumping, with the energy transfer efficiency of 54.9%. The ∼1.54 μm electroluminescence of erbium ions here is proved to originate from indirect excitation, different from the conventional impact excitation by hot electrons. Herein, the light emitting devices present a turn-on voltage of ∼13 V and onset electric field of 1.4 MV/cm. This work demonstrates the potential of preparing practical electrical-driven silicon-based light sources from erbium doped Ga 2 O 3 films. • Er doped Ga 2 O 3 films on p-Si is prepared by sputtering. • ∼1.54 μm photoluminescence is achieved by energy transfer between Ga 2 O 3 and Er. • Er ions are located at the octahedron sites of Ga ions. • ∼1.54 μm electroluminescence is realized by energy transfer in Ga 2 O 3 hosts on Si. • The light-emitting devices present the turn-on voltage of ∼13 V. [ABSTRACT FROM AUTHOR]