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Circularly polarized luminescence (CPL) with polychromatic colors has been widely studied due to its great applications in chiroptical, optoelectronics, and spintronics. However, the realization of white CPL in single‐component solid‐state materials remains a great challenge and suffers from the incompatibility between high efficient luminescence and large asymmetric discrimination. Here, by exploiting self‐trapped exciton mechanism and chirality induction strategy, a pair of 1D chiral perovskites, (RR/SS‐DMPZ)PbBr4 (where DMPZ = cis‐2,5‐dimethylpiperazine divalent cation), is reported to achieve white CPL with both high quantum yield of 28.4% and large photoluminescence asymmetry factor |glum| of 2.32 × 10−2. The crystal structures are featured by 1D double‐chain structure composed of distorted octahedra with short PbPb distances as the structural origin of the high photoluminescence yield. The high |glum| value is caused by efficient chiral induction due to the multiple hydrogen bonds between the chiral host composed of the enantiopure organic cations containing two stereocenters and the inorganic emitting guest. The self‐trapped exciton emission mechanism is demonstrated by density functional theory calculations and variable‐temperature photoluminescence and femtosecond‐transient absorption spectroscopy studies. The photo‐luminescent white light‐emitting diodes exhibit good stability and can be used as single‐component white light emitters. This work provides applicable strategies to explore single‐component white CPL emitters. [ABSTRACT FROM AUTHOR]

Rationally optimizing the photoluminescence performance via accurate structural modulation is one of most important and challenging issues for hybrid halides. Herein, a viable crystal dimensional reduction strategy is proposed to reasonably enhance the photoluminescence quantum yield (PLQY) of hybrid antimony halide. Specifically, a synthetic technique is developed and new 1D [DMPZ]SbCl5 ∙ H2O (DP‐SbCl5) is sliced to 0D [DMPZ]2SbCl6 ∙ Cl ∙ (H2O)2 (DP‐SbCl6) with crystal dimensional reduction from infinite [SbCl5]2− chain to discrete [SbCl6]3− octahedron. Comparing with nonluminescent 1D DP‐SbCl5, 0D DP‐SbCl6 displays highly efficient broadband yellow light emission with enhanced PLQY up to 75.94%. First‐principles calculation demonstrates that 0D DP‐SbCl6 features more flat and narrow band structure, which promotes the photoelectron localization and increases the quantum confinement, and finally boosts the luminescence efficiency. Together highly efficient and ultra‐stable luminescence performance enable DP‐SbCl6 as excellent down‐conversion broadband yellow phosphor to successfully fabricate white light emitting diodes with a high color rendering index of 92. This work provides a novel structural modulation strategy of crystal dimensional reduction to rationally optimize the PL performance of hybrid metal halides. [ABSTRACT FROM AUTHOR]

Recently, low-dimensional organic–inorganic hybrid metal halides have attracted considerable attention in solid-state optical application fields, especially in white-light emitting diodes (WLEDs) owing to intrinsic broadband luminescence performances. Herein, by selecting different types of organic cations as a structural decoration strategy, we designed a series of new 1D hybrid halides of A2Pb3Br10 (A = NPM, DMPDA, TMEN) based on same [Pb3Br10]4− chains composed of edge-shared [Pb3Br12]6− trimers. The low-dimensional crystal lattice results in the formation of self-trapped excitons, which leads to broadband light emissions covering the entire visible region for all A2Pb3Br10 homologues. Specifically, compound 1 exhibits yellowish-white light emission (0.34, 0.45) with a photoluminescence quantum efficiency of 2.51%. Both compounds 2 and 3 show bluish-white light emissions centered at 438 nm and 440 nm, respectively, with high color rendering index (CRI) of 96, which belongs to one of the highest values to date. The intrinsic broadband white light emissions enable them as promising candidates for single-component white-light emitting materials. [ABSTRACT FROM AUTHOR]

It remains significant to explore new types of hybrid lead halides to realize the diversifications of structural and luminescence properties due to the excellent optoelectronic performances of perovskites. Herein, by choosing various organic molecules as cationic templates, we constructed a series of new one-dimensional (1D) lead halide perovskites, namely, [DMEDA]Pb2Br6·H2O (1), [ATMPD]Pb2Br6·H2O (2) and [TMPrDA]2Pb3X10 (3: X = Br; 4: X = Cl). The crystal structures of compounds 1–4 contain 1D [Pb2Br6]2− and [Pb3X10]4− chains based on [Pb4X16] tetramer clusters as basic building units, respectively. Remarkably, compound 2 displays broadband yellow light emissions spanning the entire visible spectral range and centered at 534 nm, which can be ascribed to self-trapped excitons based on systematic characterization including time-resolved PL emission and theoretical studies. This work provides a series of new low-dimensional hybrid lead halides as prototypes to enrich the halide chemistry including crystal engineering and optoelectronic performance. [ABSTRACT FROM AUTHOR]

Recently, 2D organic–inorganic hybrid lead halide perovskites have attracted intensive attention in solid‐state luminescence fields such as single‐component white‐light emitters, and rational optimization of the photoluminescence (PL) performance through accurate structural‐design strategies is still significant. Herein, by carefully choosing homologous aliphatic amines as templates, isotypical perovskites [DMEDA]PbCl4 (1, DMEDA=N,N‐dimethylethylenediamine) and [DMPDA]PbCl4 (2, DMPDA=N,N‐dimethyl‐1,3‐diaminopropane) having tunable and stable broadband bluish white emission properties were rationally designed. The subtle regulation of organic cations leads to a higher degree of distortion of the 2D [PbCl4]2− layers and enhanced photoluminescence quantum efficiencies (<1 % for 1 and 4.9 % for 2). The broadband light emissions could be ascribed to self‐trapped excitons on the basis of structural characterization, time‐resolved PL, temperature‐dependent PL emission, and theoretical calculations. This work gives a new guidance to rationally optimize the PL properties of low‐dimensional halide perovskites and affords a platform to probe the structure–property relationship. [ABSTRACT FROM AUTHOR]

Herein, by using a structural design strategy of incorporating hetrometallic halide blocks, we prepared the first 3D bimetallic halide of [H2DABCO]2Cu6PbBr12 with new topological network based on two types of 6-connected nodes. Remarkably, this 3D framework displays highly efficient thermochromic luminescence from broadband yellow to green light emissions with remarkable stability. [ABSTRACT FROM AUTHOR]

With different transition metal (TM) complexes as structure directing agents or building units, three new multinary chalcognidometalates based on T3 supertetrahedral nanocluster of [Mn2Ga4Sn4S20]8− have been solvothermally synthesized and structurally characterized. In compound Mn2Ga4Sn4S20[Mn2(en)5]2·4H2O (1, en = ethylenediamine), the neighboring [Mn2Ga4Sn4S20]8− cores were bridged by two pairs of [Mn2(en)5]4+ complex cations via Mn–S bonds to form one-dimensional (1D) neutral chains. Compound Mn2Ga4Sn4S20[Mn(dien)2]4·2H2O (2, dien = diethylenetriamine) contained discrete [Mn2Ga4Sn4S20]8− cores separated by [Mn(dien)2]2+ cations. In compound Mn2Ga4Sn4S20[Mn(teta)]4 (3, teta = triethylenetetramine), each [Mn2Ga4Sn4S20]8− core was covalently attached by four [Mn(teta)]2+ complexes via terminal Mn–S bonds to form a neutral isolated cluster. The photocatalytic experiments indicate that compound 1 was able to degrade rhodamine B (RhB) and crystal violet (CV) under visible irradiation. Furthermore, the luminescence properties and thermal stabilities of the title compounds, as well as the second-order nonlinear optical property of 3 were also studied. [ABSTRACT FROM AUTHOR]

Four new quaternary chalcogenides, Ba4AgGaS6 ( 1), Ba4AgGaSe6 ( 2), Ba4CuInS6 ( 3), and Ba4AgInS6 ( 4), were synthesized by solid-state reactions and their structures were characterized through single-crystal X-ray diffraction. In spite of their similar chemical compositions, the flexible arrangement between the transition metals and the triel atoms leads to subtle differences in their polyanion structures. All structures feature similar [MTrQ6]8− 1D polyanionic chains (M=Cu, Ag; Tr=Ga, In; Q=S, Se), which are constructed from corner-sharing MQ4 or TrQ4 tetrahedra. However, the transition metals and triels are mixed in 1, 2, and 3, but they occupy independent crystallographic sites in 4. As a result, compounds 1- 3 belong to the known Ba2CoS3 ( Pnma No. 62) or Ba2MnS3 ( Pnma No. 62) class, whereas 4 crystallizes in its own structural type within the monoclinic P21/ c (No. 14) space group. The structural relationship among these new phases was also studied with the aid of DFT calculations and related optical properties are presented as well. [ABSTRACT FROM AUTHOR]

Abstract: One new AgI complex, [Ag2(aip)(NH3)]n (H2aip = 5-aminoisophthalic acid), has been prepared and structurally and spectroscopically characterized. The title complex crystallizes in the monoclinic system P21/c (no. 14) with a =6.975(2) Å, b =8.756(3) Å, c =16.086(6) Å, β =97.318(4)°, V=974.4(6) Å3 and Z=4. Its structure features a three-dimensional (3D) network composed of two-dimensional (2D) flexuous layer interconnected via weak hydrogen bonds. In aqueous solution, the H2aip exhibits blue emission, while the title complex with tetranuclear silver(I) cores and weak Ag…Ag bonds shows visible intense purple luminescence. [Copyright &y& Elsevier]

New Ce-based Werner type tetrahedrons were achieved for sizeselectively luminescent detection of natural carbohydrates through incorporating amide groups as both the multiple hydrogen bonding triggers and binding-signalling transductor. [ABSTRACT FROM AUTHOR]

Ba4AgGaS6 (I), Ba4AgGaSe6 (II), Ba4CuInS6 (III), and Ba4AgInS6 (IV) are prepared by solid-state reactions of the elements and/or binary chalcogenides (fused silica tube under Ar, 850-960 °C, 3-7 d). [ABSTRACT FROM AUTHOR]

New 2D perovskites contain special 2D layers formed by the mix of corner- and edge- shared with [PbX 6 ] octahedrons, and display the broadband yellow-light emissions covering the whole visible region. [Display omitted] • New 2D perovskites composed of mixed corner- and edge-shared octahedron. • Broadband emission covering the whole entire visible light. • These 2D perovskites can be fabricated as white LEDs with high CRI. Herein, we reported two new 2D perovskites of [DAPMA] 2 Pb 3 X 12 ·2H 2 O (X = Cl (1), Br (2), DAPMA = N,N-Bis(3-aminopropyl)methylamine) containing special 2D [Pb 3 X 12 ]6− layers formed by mixed corner- and edge-shared [PbX 6 ] octahedrons. Both compounds 1 and 2 exhibit broadband yellow light emissions with promising photoluminescence quantum yields of 4.84% and 3.02%, respectively. According to detailed spectroscopy characterizations, the broadband light emissions should originate from self-trapped excitons (STEs). In addition, these 2D perovskites can be fabricated as white LEDs with highest color rendering index of 96.3%. This work provides a new type of structural model to probe into the relationship between luminescence behavior and structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three new one-dimensional (1D) face-shared octahedral perovskites were synthesized by using different types of organic cations. • These 1D perovskites exhibit tunable broadband luminescence from orange to blue light emissions. • Systematical characterizations unveil that these broadband emissions are derived from the radiative recombination of self-trapped excitons due to strong electron–phonon coupling. Three new one-dimensional (1D) face-shared octahedral perovskites with unified APbBr 3 composition, namely, [DTHPE]Pb 2 Br 6 (1), [TMPDA]PbBr 3 (2) and [MPD]PbBr 3 (3) have been synthesized by using different types of organic cations. These 1D perovskites exhibit tunable broadband luminescence from orange to blue light emissions. Experimental and computational studies unveil that these broadband emissions are derived from the radiative recombination of self-trapped excitons due to strong electron–phonon coupling. [ABSTRACT FROM AUTHOR]