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Despite remarkable luminescent performance of 0D lead halide perovskites, achieving highly efficient blue light emission is extremely challenging and crucial for this domain. Considering the high toxicity of Pb2+ ion, it is significant to explore water‐stable lead‐free 0D halides as highly efficient and stable blue emitting materials. To address these issues, a family of 0D hybrid zinc halides of AZnBr4 (A = EP, BP, and TMPDA) based on discrete [ZnBr4]2− tetrahedrons is herein reported as desirable blue light emitters. The wide band gaps enable these 0D halides to display highly efficient blue light emissions (452–485 nm) with highest photoluminescence quantum yield (PLQY) of 35.47%. More importantly, all these 0D halides present extraordinary chemical stabilities in humid air and water for one month, and are also capable of withstanding extreme pH conditions in the range of 0–14, likely the widest observed pH range for perovskites. Notably, the ultrahigh chemical stabilities of 0D zinc halides are nearly unmatchable among all known literature perovskite materials to the best of the authors' knowledge. Combined superiorities of unusual blue light emission, promising PLQY, ultrahigh stability, and non‐toxicity highlight the potential optoelectronic applications in wide chemical environments for these 0D zinc halides. [ABSTRACT FROM AUTHOR]

Hybrid organic–inorganic lead halide perovskites (HOIPs) possess significant photoelectric characteristics for solar energy conversion, but the presence of lead causes issues for eco-friendly applications. Halide double perovskites represent a green option for application in the optoelectronic field, especially X-ray detection systems. Despite the great efforts, the exploration of large-size lead-free iodide-based hybrid double perovskite single crystals for X-ray detection has been unsuccessful. Herein, we demonstrate that a large single crystal of the 2D (two-dimensional) semiconducting perovskite (C6H16N2)2CuBiI8·0.5H2O can serve as an X-ray detection candidate. A perovskite crystal, as large as 35 × 31 × 3 mm3, was grown using a low-cost, simple cooling solution approach. To the best of our knowledge, this is the first time a centimeter-sized 2D BiCu iodide double perovskite single crystal has been used for X-ray detection. The perovskite crystal exhibited unique properties for X-ray detection, such as a significant X-ray absorption coefficient, considerable μτ product, and low trap density. Moreover, X-ray detection with a sensitivity of 5.51 μC Gyair−1 cm−2 was achieved based on a single crystal. This work opens new ways to explore specially designed organic cations for stabilizing 2D HOIPs that show great potential in optoelectronics. [ABSTRACT FROM AUTHOR]

Mn2+ doped colloidal three‐dimensional (3D) lead halide perovskite nanocrystal (PNC) has attracted intensive research attention; however, the low exciton binding energy and fatal optical instability of 3D PNC seriously hinder the optoelectronic application. Therefore, it remains significant to explore new stable host perovskite with strongly bound exciton to realize more desirable luminescent property. In this work, we utilized bulk one‐dimensional (1D) hybrid perovskite of [AEP]PbBr5 ⋅ H2O (AEP=N‐aminoethylpiperazine) as structural platform to rationally optimize the luminescent property by a controllable Mn2+ doping strategy. Significantly, the series of Mn2+‐doped 1D [AEP]PbBr5 ⋅ H2O show enhanced energy transfer efficiency from the strongly bound excitons of host material to 3d electrons of Mn2+ ions, resulting in tunable broadband light emissions from weak yellow to strong red spectral range with highest photoluminescence quantum yield up to 28.41 %. More importantly, these Mn2+‐doped 1D perovskites display ultrahigh structural and optical stabilities in humid atmosphere, water and high temperature exceeding the conventional 3D PNC. Combined highly efficient, tunable and stable broadband light emissions enable Mn2+‐doped 1D perovskite as excellent down‐converting phosphor showcasing the potential application in white light emitting diode. This work not only provides a profound understanding of low‐dimensional perovskites but also opens a new way to rationally design high‐performance broadband light emitting perovskites for solid‐state lighting and displaying devices. [ABSTRACT FROM AUTHOR]

One new type of hybrid lead halide of [DTHPE]2Pb3Cl10 has been synthesized and characterized containing a one-dimensional (1D) wavelike [Pb3Cl10]4− chain based on a corner-shared [Pb3Cl11] cluster. Remarkably, this cluster-based 1D chain displays intrinsic broadband white light emission with a high quantum efficiency of 19.45% exceeding those of previously reported typical two-dimensional perovskites. [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]

Considering the instability and low photoluminescence quantum yield (PLQY) of blue‐emitting perovskites, it is still challenging and attractive to construct single crystalline hybrid lead halides with highly stable and efficient blue light emission. Herein, by rationally introducing d10 transition metal into single lead halide as new structural building unit and optical emitting center, we prepared a bimetallic halide of [(NH4)2]CuPbBr5 with new type of three‐dimensional (3D) anionic framework. [(NH4)2]CuPbBr5 exhibits strong band‐edge blue emission (441 nm) with a high PLQY of 32 % upon excitation with UV light. Detailed photophysical studies indicate [(NH4)2]CuPbBr5 also displays broadband red light emissions derived from self‐trapped states. Furthermore, the 3D framework features high structural and optical stabilities at extreme environments during at least three years. To our best knowledge, this work represents the first 3D non‐perovskite bimetallic halide with highly efficient and stable blue light emission. [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]

By using transition-metal (TM) complex cationic dyes as structure-directing agents and photosensitizers, a series of inorganic–organic hybrid metal halides, namely, [TM(2,2′-bipy)3]AgPb2I7 [TM = Ni (1), Co (2) and Zn (3)], [Co(2,2′-bipy)3]CuPb2Br7 (4) and [TM(2,2′-bipy)3]AgPb2Br7 [TM = Ni (5) and Fe (6)], have been solvothermally prepared and structurally characterized. Compounds 1–3 feature 1D [AgPb2I7]2− chains built from the condensation of [Ag2I6] dimers and [Pb4I14] tetramers, and compounds 4, 5 and 6 contain similar 1D [CuPb2Br7]2− and [AgPb2Br7]2− chains, respectively. UV-Vis diffuse reflectance measurements reveal narrow band gaps of 1.75–2.18 eV for compounds 1–6, which lead to efficient and stable photocatalytic degradation activities over organic pollutants under visible light irradiation. Among the title compounds, sample 5 shows the highest photocatalytic degradation activity. The possible mechanism for their stable photocatalytic activities is proposed based on the experimental and theoretical studies. [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]