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Red-emitting CsPbI3 perovskite materials are still limited in various commercial applications because of their stability being related to the morphology and dimension. In this paper, a solvothermal method was developed to fabricate CsPbI3 perovskite nanomaterials with governable morphologies (e.g., nanoplatelets (NPLs) to nanocubes (NCs)) and dimensions ranging from the zero-dimensional (0D) Cs4PbI6 to the three-dimensional (3D) CsPbI3. By adjusting the amount of Cs precursor solutions, the photoluminescence (PL) peak position of the samples was tuned over the whole red-emitting region (from 607 to 700 nm). In addition, the reaction temperature affected the PL properties of the samples and demonstrated that temperature was critical to control the performance of CsPbI3 perovskite materials. Furthermore, sodium dodecyl benzene sulfonate (SDBS) was chosen as the additive to improve the stability of the prepared samples. The result provided an approach to get CsPbI3 perovskite nanocrystals with stabile PL. Finally, CsPbI3 NPLs embedded in the polystyrene film displayed bright and stable white light emission. [ABSTRACT FROM AUTHOR]

ZnO flowers consisting of single crystal nanosheets with exposed { 1   1 ¯   0   0 } facets were fabricated from trisodium citrate via hydrothermal at 180 °C. The single crystal nanosheet has the thickness of about 70 nm and a well-crystalline structure with dominant surfaces as { 1   1 ¯   0   0 } planes. The site-specific nucleation-growth process contributes to the formation of hierarchical flower-like ZnO structures. The ZnO flowers exhibited white emission. The visible emission gradually decreased with time and the UV emission suggests that the recombined rate of photogenerated electrons and holes of samples varied with the synthesis parameters. The ZnO flowers displayed an enhanced photocatalytic performance compared with ZnO microspheres. The maximized exposure of the reactive { 1   1 ¯   0   0 } facets also favors the enhanced photocatalytic performance. Additionally, the special loose structural feature with an open microstructure has more important influences on the photocatalytic activity than specific surface area. [ABSTRACT FROM AUTHOR]

Some of the metal vanadates have special self-activated luminescence. In order to further enrich its luminous color, luminescent impurity ions can be introduced into its lattice. The interaction between the self-activated emission and the impurity-related emission remains to be studied. In this work, the synergism between the two kinds of emission in LiCa 3 ZnV 3 O 12 was explored from these three aspects: lattice distortion, energy transfer and temperature effect. Eu 3+ ions replace Ca 2+ ions in the lattice of LiCa 3 ZnV 3 O 12 , leading to a lattice contraction of the LCZV host, which depresses the self-activating emission around 500 nm. The characteristic linear emissions of Eu 3+ ions are also observed benefiting from the energy transfer from [VO 4 ] 3- to Eu 3+ . Since the temperature quenching effect is more sensitive for the self-activated emission than that for the Eu 3+ -related ones, the phosphor can be applied as a luminescent temperature sensor, with the absolute and relative temperature sensitivities of 0.012 K -1 and 1.56% K -1 , respectively., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The stability of metal halide perovskite (CsPbX 3 , X = Cl, Br, and I) nanocrystals (NCs) is crucial for their practical applications. In this paper, perovskite NCs were synthesized in situ in lead-based metal-organic frameworks (Pb-MOFs: [Pb 2 (1,3,5-HBTC) 2 (H 2 O) 4 ]·H 2 O), and we obtained stable and bright luminescence composites with different colors. Namely, CsPbBr 3 @Pb-MOF composites were created by the in situ growth of CsPbBr 3 crystals (NCs) on Pb-MOF, which had high ion resistance, bright photoluminescence (PL), and excellent stability. The composites still had bright luminescence after 11 months of storage. The PL intensity of green-emitting CsPbBr 3 @Pb-MOF composites was increased compared with as-prepared CsPbBr 3 NCs. Bright and stable blue- and red-emitting CsPbX 3 @Pb-MOF composites were obtained by adjusting the amount of PbX 2 (X = Cl, Br, and I) in the synthesis process. These CsPbX 3 NCs were homogeneously distributed in Pb-MOF substrates. The growth of CsPbX 3 NCs in Pb-MOFs prevented NC aggregation and decreased surface defects against nonradiative recombination during emitting. Thus, the PL lifetime and stability were improved. Furthermore, white light-emission diodes were prepared using three color CsPbX 3 @Pb-MOF composites with Commission Internationale de I'Eclairage color coordinates of (0.296, 0.316). This result provided an efficient way to overcome the limitation of chemical solution synthesis and improve the stability of CsPbX 3 NCs.

TGA capped CdTe QDs have been encapsulated in miroporous ZIF-8, with no obvious deterioration of their photoluminescence property. The resulted CdTe QD@ZIF-8 composites show a higher luminescent stability in various buffer solution. The material has successfully been used as a luminescent indicator for the detection of Cu 2+ and Fe 2+ ions. The luminescence of CdTe QD@ZIF-8 composite quenches only in the presence of Cu 2+ or Fe 2+ ions. The linear ranges of detection have been estimated as 1~50 uM for Cu 2+ ions and 1~60 uM for Fe 2+ ions, respectively. A "competing transmission" mechanism has been proposed to explain the selectivity of the sensor to detecting Cu 2+ and Fe 2+ ions. Luminescent quenching can only occurred when the bonding power of QD surface surpasses the adsorptivity of the outside ZIF-8 to the metal ions.