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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]

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]