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ZnO nano- and microstructures co-doped with Eu and Li with different nominal concentrations of Li were grown using a solid vapor method. Different morphologies were obtained depending on the initial Li content in the precursors, varying from hexagonal rods which grow on the pellet when no Li is added to ribbons to sword-like structures growing onto the alumina boat as the Li amount increases. The changes in the energy of the crystallographic planes leading to variations in the growth directions were responsible for these morphological differences, as Electron Backscattered Diffraction analysis shows. The crystalline quality of the structures was investigated by X-ray diffraction and Raman spectroscopy, showing that all the structures grow in the ZnO wurtzite phase. The luminescence properties were also studied by means of both Cathodoluminescence (CL) and Photoluminescence (PL). Although the typical ZnO luminescence bands centered at 3.2 and 2.4 eV could be observed in all cases, variations in their relative intensity and small shifts in the peak position were found in the different samples. Furthermore, emissions related to intrashell transitions of Eu3+ ion were clearly visible. The good characteristics of the luminescent emissions and the high refraction index open the door to the fabrication of optical resonant cavities that allow the integration in optoelectronic devices. To study the optical cavity behavior of the grown structures, µ-PL investigations were performed. We demonstrated that the structures not only act as waveguides but also that Fabry–Perot optical resonant modes are established inside. Quality factors around 1000 in the UV region were obtained, which indicates the possibility of using these structures in photonics applications.

ZnO nano- and microstructures co-doped with Eu and Li with different nominal concentrations of Li were grown using a solid vapor method. Different morphologies were obtained depending on the initial Li content in the precursors, varying from hexagonal rods which grow on the pellet when no Li is added to ribbons to sword-like structures growing onto the alumina boat as the Li amount increases. The changes in the energy of the crystallographic planes leading to variations in the growth directions were responsible for these morphological differences, as Electron Backscattered Diffraction analysis shows. The crystalline quality of the structures was investigated by X-ray diffraction and Raman spectroscopy, showing that all the structures grow in the ZnO wurtzite phase. The luminescence properties were also studied by means of both Cathodoluminescence (CL) and Photoluminescence (PL). Although the typical ZnO luminescence bands centered at 3.2 and 2.4 eV could be observed in all cases, variations in their relative intensity and small shifts in the peak position were found in the different samples. Furthermore, emissions related to intrashell transitions of Eu3+ ion were clearly visible. The good characteristics of the luminescent emissions and the high refraction index open the door to the fabrication of optical resonant cavities that allow the integration in optoelectronic devices. To study the optical cavity behavior of the grown structures, µ-PL investigations were performed. We demonstrated that the structures not only act as waveguides but also that Fabry–Perot optical resonant modes are established inside. Quality factors around 1000 in the UV region were obtained, which indicates the possibility of using these structures in photonics applications.

This Data article presents the absorption coefficients of Lead Iodine perovskites using 14 different organic cations. In addition, the absorption coefficients have been split into inter-atomic species components in order to quantify all of the contributions. For more details on the methodology, interpretation and discussion, refer to the full length article entitled "Effect Of the organic cation on the optical properties of lead iodine perovskites". https://doi.org/10.1016/j.solmat.2019.110022 Data may be useful for future research, and to identify the contribution of different species to the absorption.

This Data article presents the absorption coefficients of Lead Iodine perovskites using 14 different organic cations. In addition, the absorption coefficients have been split into inter-atomic species components in order to quantify all of the contributions. For more details on the methodology, interpretation and discussion, refer to the full length article entitled "Effect Of the organic cation on the optical properties of lead iodine perovskites". https://doi.org/10.1016/j.solmat.2019.110022 Data may be useful for future research, and to identify the contribution of different species to the absorption.

AbstractThe search for long‐lived red and NIR fluorescent dyes is challenging and hitherto scarcely reported. Herein, the viability of aza‐BODIPY skeleton as a promising system for achieving thermal activated delayed fluorescent (TADF) probes emitting in this target region is demonstrated for the first time. The synthetic versatility of this scaffold allows the design of energy and charge transfer cassettes modulating the stereoelectronic properties of the energy donors, the spacer moieties and the linkage positions. Delayed emission from these architectures is recorded in the red spectral region (695–735 nm) with lifetimes longer than 100 μs in aerated solutions at room temperature. The computational‐aided photophysical study under mild and hard irradiation regimes disclose the interplay between molecular structure and photonic performance to develop long‐lived fluorescence red emitters through thermally activated reverse intersystem crossing. The efficient and long‐lasting NIR emission of the newly synthesized aza‐BODIPY systems provides a basis to develop advanced optical materials with exciting and appealing photonic response.

AbstractThe search for long‐lived red and NIR fluorescent dyes is challenging and hitherto scarcely reported. Herein, the viability of aza‐BODIPY skeleton as a promising system for achieving thermal activated delayed fluorescent (TADF) probes emitting in this target region is demonstrated for the first time. The synthetic versatility of this scaffold allows the design of energy and charge transfer cassettes modulating the stereoelectronic properties of the energy donors, the spacer moieties and the linkage positions. Delayed emission from these architectures is recorded in the red spectral region (695–735 nm) with lifetimes longer than 100 μs in aerated solutions at room temperature. The computational‐aided photophysical study under mild and hard irradiation regimes disclose the interplay between molecular structure and photonic performance to develop long‐lived fluorescence red emitters through thermally activated reverse intersystem crossing. The efficient and long‐lasting NIR emission of the newly synthesized aza‐BODIPY systems provides a basis to develop advanced optical materials with exciting and appealing photonic response.