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Halide double perovskites have recently emerged as a promising environmentally friendly optoelectronic and photovoltaic material for their inherent thermodynamic stability, high defect tolerance, and appropriate band gaps. However, to date, no ferroelectric material based on halide double perovskites has been discovered. Herein, by hetero‐substitution of lead and cation intercalation of n‐propylamine, the first halide double perovskite ferroelectric, (n‐propylammonium)2CsAgBiBr7 (1), is reported and it exhibits distinct ferroelectricity with a notable saturation polarization of about 1.5 μC cm−2. More importantly, single‐crystal photodetectors of 1 exhibit extraordinary performance with containing high on/off ratios of about 104, fast response rates of 141 μs, and detectivity as high as 5.3×1011 Jones. This finding opens a new way to design high‐performance perovskite ferroelectrics, and provides a viable approach in the search for stable and lead‐free optoelectronic materials as an alternative to the lead‐containing system. [ABSTRACT FROM AUTHOR]

Halide double perovskites have recently emerged as a promising environmentally friendly optoelectronic and photovoltaic material for their inherent thermodynamic stability, high defect tolerance, and appropriate band gaps. However, to date, no ferroelectric material based on halide double perovskites has been discovered. Herein, by hetero‐substitution of lead and cation intercalation of n‐propylamine, the first halide double perovskite ferroelectric, (n‐propylammonium)2CsAgBiBr7 (1), is reported and it exhibits distinct ferroelectricity with a notable saturation polarization of about 1.5 μC cm−2. More importantly, single‐crystal photodetectors of 1 exhibit extraordinary performance with containing high on/off ratios of about 104, fast response rates of 141 μs, and detectivity as high as 5.3×1011 Jones. This finding opens a new way to design high‐performance perovskite ferroelectrics, and provides a viable approach in the search for stable and lead‐free optoelectronic materials as an alternative to the lead‐containing system. [ABSTRACT FROM AUTHOR]

Optically anisotropic crystal NaPO 2 (NH) 3 (CO) 2 achieves effective balance between wide bandgap and large birefringence owing to the π-conjugation confinement effect in the constituent [PO 2 (NH) 3 (CO) 2 ]− building units. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The control of helicity at the supramolecular level is a fascinating challenge for chemists. This paper provides a short mini-review of recent advances in the design and construction of helical coordination polymers that are categorized based on designing different types of bridging ligands. Chiral coordination polymers based on helical topologies built from chiral or achiral bridging ligands and their potential applications are also presented. [Copyright &y& Elsevier]

Six hydrogen-bonded silver(I) complexes, Ag(4-abaH)2(NO3) (1), [Ag(4-abaH)2(NO3)]n (2), {[Ag(4-aba)(4-abaH)] · H2O}n (3), {[Ag(4,4′-bipy)(H2O)](4-aba)0.5(NO3)0.5 · (H2O)0.5}n (4), [Ag[(3-abaH0.5)2] (5), and {[Ag(3-aba)] · H2O}n (6) (4-abaH=4-aminobenzoic acid, 3-abaH=3-aminobenzoic acid), have been synthesized and characterized by single-crystal X-ray diffraction analyses. In 1, 4-abaH serves as a monodentate ligand coordinating to Ag(I) through its nitrogen atom, while uncoordinated carboxylic group links (4-abaH)-Ag-(4-abaH) into a one-dimensional metallic carboxylic synthon. 2 may be regarded as an extension of 1 into a two-dimensional carboxylic synthon through NO3 − bridging two adjacent Ag(I) centers. In 3, 4-abaH in a monodentate mode and 4-aba in a μ-N,O bridging mode link three-coordinated Ag(I) to form a one-dimensional swallow-like chain, which is further extended into a two-dimensional layer structure through inter-chain hydrogen bonding interactions. The alternating Ag(I) and 4,4′-bipy in 4 give rise to a slightly distorted linear chain, which is further extended into a two-dimensional layer through the completely overlapping and off-set stacking interactions. The hydrogen bonds involving in weakly coordinated aqueous molecules and 4-aba further extend it into a three-dimensional framework. In 5, the inter-molecular hydrogen bonding and π–π stacking interactions extend Ag[(3-abaH0.5)2] into a two-dimensional supramolecular architecture. In 6, 3-aba in a μ3-N,O,O′ coordination mode links three three-coordinated Ag(I) into a two-dimensional network. Uncoordinated aqueous molecules and the adjacent 3-aba oxygen atoms form intermolecular hydrogen bonds. [Copyright &y& Elsevier]

A novel organic–inorganic hybrid compound [(Cu(bIz)2)]2[{Cu(bIz)2}2Mo8O26] (1) has been synthesized from solvothermal reaction of benzimidazole, NaMoO4 and MoO3 with CuCl2·2H2O in H2O/CH3OH solution and characterized by single-crystal X-ray diffraction analysis. Crystallographic data for 1: monoclinic, space group C2/c, a=23.6823(2) A˚, b=20.2669(5) A˚, c=16.0220(3) A˚, β=109.030(1), Z=8, V=7269.8(2) A˚3. The compound consists of a centrosymmetric β-octamolybdate-supported complex anion [{Cu(bIz)2}2Mo8O26]2−, and two bis-bIz coordinated Cu(I) cations. The hydrogen bonds between [{Cu(bIz)2}2Mo8O26]2− anions generate a interesting 1D ladder. TG analysis, UV–Vis spectra and fluorescent spectroscopy of the compound were also studied. [Copyright &y& Elsevier]

The reaction of pyridine-2-thiol with AgBF4 and AgClO4 in MeCN gave rise to polymeric compounds [{Ag(HPyS)2}2(BF4)2]n (1) and [{Ag(HPyS)2}2(ClO4)2]n (2) (HPyS=pyridine-2-thione), respectively, while the similar reaction of pyridine-2-thiol with AgNO3 resulted in a polymeric compound [{Ag4(HPyS)6}(NO3)4]n (3). X-ray single-crystal diffraction analyses showed that the cations of both 1 and 2 possess a single-metal-atom chain structure but that of 3 is a double-metal-atom chain structure. The difference between 1 (or 2) and 3 showed counterion effect in polymerization of silver-thione compounds. In the presence of water, the treatment of pyridine-2-thiol with AgBF4 in DMF at 0 °C generated a polymeric compound [Ag(SPy)]n (4) (Spy=pyridine-2-thiolate) with graphite-like layered array of silver ions. Compound 4 can convert into its isomer [Ag6(SPy)6]n (5) through soaking in DMF for 1 month. However, the similar reaction of pyridine-2-thiol with AgBF4 in MeCN–H2O (v:v=40:1) at room temperature gave another layered polymeric compound [{Ag5(Spy)4(HPyS)}BF4]n (6). The preparation of 4, 5, and 6 showed that temperature and solvent exert influence on formation of silver-thiolate polymers. The reaction of AgNO3 with K2i-mnt (i-mnt=2,2-dicyanoethene-1,1,-dithiolate) and pyridine-2-thiol gave a polymer [Ag4(μ4-i-mnt)2(μ-HPyS)2(μ-HPyS)4/2]n (7) with one-dimensional (1-D) chain structure consisting of Ag4 square planar cluster units linked by 1H-pyridine-2-thione ligand. The treatment of AgNO3 with NaS2CNEt2 and pyridine-2-thiol in DMF resulted in another polymeric compound [Ag4(μ3-S2CNEt2)2(μ2-SPy)4/2]n (8). The preparation and characterization of these polymeric compounds demonstrated that polymerization of silver(I)-thione and silver(I)-thiolate complexes is tunable through controlling reaction conditions. Semiconducting property studies of 1–8 demonstrated that the electrical conductivity of 4 is 2.04×10−5 S cm−1 at 25 °C and increases as temperature rises, and those of 1–3 and 5–8 are in the range of 1×10−12–1×10−15 S cm−1 at room temperature and independent on the temperature, indicating that 1 is a semiconductor and the others are insulators. [Copyright &y& Elsevier]

Two new dicyanamide (dicyanamide=[N(CN)2]−, dca) bridged complexes, [Cu(μ1,5-dca)2(phen)]n (1) and [Cd(μ1,5-dca)2(py)2]n (2) have been synthesized and their structures have been determined by X-ray crystallography diffraction. Complex 1 crystallizes in the monoclinic space group P2(1)/c with a=10.1502(3), b=10.9815(4), c=14.5839(4) A˚ and Z=4. The adjacent copper atoms are connected by single end-to-end dca bridges to form a chain structure along the b axis. The chains are linked via Cu⋯N weak interactions to give rise to a 2D layer structure, which furthermore into a 3D structure by the π–π interaction between aromatic rings of adjacent layers. Complex 2 crystallizes in the monoclinic space group C2/m with a=6.6849(10), b=17.476(2), c=13.231(2) A˚ and Z=4. The cadmium(II) center is six-coordinated with a distorted octahedral geometry, bounded to four N atoms of four dca ligands and two N atoms of two-chelated py ligands. Neighbor Cd(II) atoms are linked by the double end-to-end dca bridges to generate a chain structure, which result in a 2D layer structure through the π–π interactions between the adjacent chains with distances 3.641 A˚. EPR and magnetic results of 1 suggest that the complex exhibits a weak ferromagnetic interaction through Cu&z.sbnd;N&z.tbnd6;C&z.sbnd;N&z.sbnd;C&z.tbnd6;N&z.sbnd;Cu pathways. [Copyright &y& Elsevier]

Two new heterometallic complexes, [Cu(en)(H2O)]2[Fe(CN)6]·4H2O (1) and [Cu(en)2][KFe(CN)6] (2), have been isolated from the reactions of CuCl2 and en with K3[Fe(CN)6] in different molar ratios. Both complexes have been characterized by X-ray analyses, IR spectra and elemental analyses. Complex 1 is a cyanide bridged bimetallic assembly, its crystal structure consists of a two-dimensional polymeric sheet with two different rings, one a four-membered square ring and another a 12-membered hexagonal ring. The Fe(II) ion of 1 has two terminal, two linear bridging and two 1,1 en-on bridging cyanide groups. In the crystal structure of 2, the neighboring [Fe(CN)6]3− units are bridged by the K+ and the [K[Fe(CN)6]]2− units forming a three-dimensional network structure. The [Cu(en)2]2+ units fill in the holes of the network acting as counter cations and charge compensations. Variable temperature magnetic susceptibility studies of 1 indicate that the complex exhibits ferromagnetic interaction between the Cu(II) ions. [Copyright &y& Elsevier]

Presents a fitting program of irreducible tensor operator for the calculation of J couplings. Energy levels of paramagnetic spin clusters; Coupling constants of the clusters; Magnetic susceptibility.

Controllable arrangement of different ligands in a single assembly will not only bring increased complexity but also offers a new route to fine‐tune the function of the designed architecture. We report here a combinatorial self‐assembly with enPd(NO3)2 and three different ligands (L1–3), which gave rise to a family of six palladium‐organic cages (C1‐6) with systematically varied shapes and cavities, including three new heteroleptic (Pd5L12L2, Pd5L12L3, Pd4L2L3), one new homoleptic (Pd4L32) cages, and two known homoleptic (Pd6L14, Pd4L22) cages. Emergent functions due to the fusion of two half cavities on the heteroleptic cages from their parent homoleptic cages have been observed: the heteroleptic cages can form ternary complexes by co‐encapsulation of both aromatic and aliphatic guests, while their homoleptic counterparts can only form binary complexes. Such a forced co‐encapsulation effect endows the heteroleptic cages with enhanced catalytic power for the Knoevenagel condensation. [ABSTRACT FROM AUTHOR]

Controllable arrangement of different ligands in a single assembly will not only bring increased complexity but also offers a new route to fine‐tune the function of the designed architecture. We report here a combinatorial self‐assembly with enPd(NO3)2 and three different ligands (L1–3), which gave rise to a family of six palladium‐organic cages (C1‐6) with systematically varied shapes and cavities, including three new heteroleptic (Pd5L12L2, Pd5L12L3, Pd4L2L3), one new homoleptic (Pd4L32) cages, and two known homoleptic (Pd6L14, Pd4L22) cages. Emergent functions due to the fusion of two half cavities on the heteroleptic cages from their parent homoleptic cages have been observed: the heteroleptic cages can form ternary complexes by co‐encapsulation of both aromatic and aliphatic guests, while their homoleptic counterparts can only form binary complexes. Such a forced co‐encapsulation effect endows the heteroleptic cages with enhanced catalytic power for the Knoevenagel condensation. [ABSTRACT FROM AUTHOR]

All‐inorganic α‐phase CsPbI3 perovskite with a suitable bandgap and superb optoelectronic properties is transforming the landscape of perovskite photovoltaics, but its long‐term lability associated with "soft" ionic lattice still imposes a great challenge for practical applications. Herein, a unique solid‐solution fluorination strategy is proposed to deliver an "ideal" perovskite matrix of α‐phase CsPbI3 abundant with F ions through interlocking the soft lattice of CsPbI3 with cubic‐phase CsF·3/2HF. Such a sublattice interlocking can not only stabilize the soft lattice of α‐phase CsPbI3 perovskite nanocrystals but also passivate their notorious surface defects, thereby producing a "rigid" solid‐solution‐type perovskite/fluoride CsPbI3/CsF (termed as CsPbI3:F) nanocomposite with excellent long‐term stability and a near‐unity photoluminescence efficiency. Of particular note is that these CsPbI3:F nanocomposites can work well as effective grain boundary anchors to significantly improve the photovoltaic performance of perovskite solar cells because of their F‐rich perovskite lattice, achieving a T80 stability of 1500 h under continuous maximum power point tracking and AM 1.5G illumination without the need for encapsulation. This work paves a new way to deliver perovskite materials with desirable properties for photovoltaics. [ABSTRACT FROM AUTHOR]

n‐C4H10 and iso‐C4H10 are both important petrochemical raw materials. Considering the coexistence of the isomers in the production process, it is necessary to achieve their efficient separation through an economical way. However, to obtain high‐purity n‐C4H10 and iso‐C4H10 in one‐step separation process, developing iso‐C4H10‐exclusion adsorbents with high n‐C4H10 adsorption capacity is crucial. Herein, we report a cage‐like MOF (SIFSIX‐Cu‐TPA) with small windows and large cavities which can selectively allow smaller n‐C4H10 enter the pore and accommodate a large amount of n‐C4H10 simultaneously. Adsorption isotherms reveal that SIFSIX‐Cu‐TPA not only completely excludes iso‐C4H10 in a wide temperature range, but also exhibits a very high n‐C4H10 adsorption capacity of 94.2 cm3 g−1 at 100 kPa and 298 K, which is the highest value among iso‐C4H10‐exclusion‐type adsorbents. Breakthrough experiments show that SIFSIX‐Cu‐TPA has excellent n/iso‐C4H10 separation performance and can achieve a record‐high productivity of iso‐C4H10 (3.2 mol kg−1) with high purity (>99.95 %) as well as 3.0 mol kg−1 of n‐C4H10 (>99 %) in one separation circle. More importantly, SIFSIX‐Cu‐TPA can realize the efficient separation of butanes at different flow rates, temperatures, as well as under high humid condition, which indicates that SIFSIX‐Cu‐TPA can be deemed as an ideal platform for industrial butane isomers separation. [ABSTRACT FROM AUTHOR]

Transition metal ions, such as Cr3+, Fe3+, and Ni2+, are widely recognized activators for efficient broadband near‐infrared (NIR) phosphors. However, the potential of Mn2+ ions as NIR‐emitting activators is relatively overlooked due to their typically narrowband emission in the visible spectral region and relatively weak absorption. Herein, a heavy Mn2+‐doped Zn1‐xAl2O4: xMn2+ (ZAO: xMn2+) phosphor is presented that exhibits a single NIR emission band peaked at 830 nm with a bandwidth of 135 nm under excitation at 450 nm. Through comprehensive structural and spectral analysis, this NIR band is attributed to the emission originating from Mn2+ ions within the MnO6 octahedra. Importantly, the formation of Mn2+–Mn2+ dimers breaks the spin‐forbidden rule and significantly enhances the transition probability, as supported by the excited state dynamic analysis. Consequently, the optimal ZAO: 0.70Mn2+ sample shows high internal/external photoluminescence quantum yields of 85.8%/36.9%, along with good thermal stability demonstrated by the emission intensity at 423 K retains 60% of that at 298 K. Finally, a prototype NIR pc‐LED device is fabricated by combining ZAO: 0.70Mn2+ phosphor with a 450 nm blue diode chip, generating an NIR output power of 28.84 mW at 100 mA. This study provides novel insights into high‐performance Mn2+‐activated NIR phosphors. [ABSTRACT FROM AUTHOR]

Examines the reactivity of the tetraselenomolybdate. What full anisotropic refinements of the structure led to; Dependency of chemical shifts; How observations were obtained.

With the development of light-emitting diodes (LEDs) display and lighting industry, new requirements have been put forward for phosphors. Traditional syntheses of phosphors face the problems of slow temperature increase, long holding time and corresponding larger particle size. In this work, a co-precipitation combined with induction heating method was developed for the fast and efficient synthesis of Lu 2.97 Al 5 O 12 :0.03Ce3+ (LuAG:0.03Ce) phosphors. The effects of calcination temperature and holding time on the morphology and luminescence properties were investigated. The phosphor synthesized at 1600 °C for 10 min (10 min@1600 °C) has an average particle size of 500 nm, and exhibits good luminescence properties and thermal stability (maintaining 92.04 % of room temperature light intensity at 200 °C). The luminescence intensity and the external quantum efficiency (EQE) of the phosphor (60 min@1500 °C) are higher than those of a commercial phosphor. The light source fabricated with phosphor ceramic prepared by the phosphor (10 min@1500 °C) shows a luminous efficacy (LE) of 193 lm/W. Therefore, co-precipitation combined with induction heating is an energy-saving and promising method for the synthesis of phosphor. [ABSTRACT FROM AUTHOR]

To realize the high-brightness of yellow light-emitting diodes (LEDs), the yellow-emitting phosphor ceramics with high luminous efficiency (LE) are urgently explored. Based on the idea of spectrum regulation, the Lu 3 -x-y Gd y Al 5 O 12 : x Ce3+ (LuGdAG:Ce) phosphor ceramics were prepared via vacuum solid-state sintering. The effect of Gd3+ and Ce3+ content on the structure, luminescence and thermal properties of LuAG:Ce ceramics were investigated. The distortion ratio (D) of CeO 8 and bandgap were effectively modified via Gd3+ doping, resulting in massive red-shifting of Ce3+ emission (513→561 nm). The LEDs lighting encapsulated by LuGdAG:Ce ceramics changes from green to yellow. Importantly, the yellow LEDs with a LE up to 139.0 lm/W@180 W and a warm correlated color temperature (CCT) of 3620 K were achieved based ceramic Ce07Gd9. The LuGdAG:Ce phosphor ceramic has the best of luminescence performance in phosphor-converted yellow LEDs lighting so far, which is considered to be the highly promising color converter. [ABSTRACT FROM AUTHOR]

Assembly of 4-aminosalicyclic acid (H2L) and Ag(I) in MeCN/H2O gave rise to a novel corrugated sheet polymer {[Ag(HL−)]·H2O}n. X-ray structural analysis reveals that Ag(I) is coordinated by three different HL− ligands in a distorted trigonal geometry and HL− links three different Ag(I) in a μ3-bridge mode forming a two-dimensional sheet structure with curvature. The separation of the carboxylate-bridged Ag⋯Ag and the distance of adjacent sheets are 2.7720(6) and 4.24 A˚, respectively. [Copyright &y& Elsevier]

The one‐step efficient separation of high‐purity C2H4 from C2H4/C2H6 mixtures by hydrogen‐bonded organic frameworks (HOFs) faces two problems: lack of strategies for constructing stable pores in HOFs and how to obtain high C2H6 selectivity. Herein, we have developed a microporous Mortise‐Tenon‐type HOF (MTHOF‐1, MT is short for Mortise‐Tenon structure) with a new self‐assembly mode for C2H4/C2H6 separation. Unlike previous HOFs which usually possess discrete head‐to‐head hydrogen bonds, MTHOF‐1 is assembled by unique consecutive side‐by‐side hydrogen bonds, which result in mortise‐and‐tenon pores decorated with orderly arranged amide groups and benzene rings. As expected, MTHOF‐1 exhibits excellent stability under various conditions and shows clear separation trends for C2H6/C2H4. The IAST selectivity is as high as 2.15 at 298 K. More importantly, dynamic breakthrough experiments have demonstrated that MTHOF‐1 can effectively separate the C2H6/C2H4 feed gas to obtain polymer‐grade C2H4 in one step even under high‐humidity conditions. [ABSTRACT FROM AUTHOR]

The one‐step efficient separation of high‐purity C2H4 from C2H4/C2H6 mixtures by hydrogen‐bonded organic frameworks (HOFs) faces two problems: lack of strategies for constructing stable pores in HOFs and how to obtain high C2H6 selectivity. Herein, we have developed a microporous Mortise‐Tenon‐type HOF (MTHOF‐1, MT is short for Mortise‐Tenon structure) with a new self‐assembly mode for C2H4/C2H6 separation. Unlike previous HOFs which usually possess discrete head‐to‐head hydrogen bonds, MTHOF‐1 is assembled by unique consecutive side‐by‐side hydrogen bonds, which result in mortise‐and‐tenon pores decorated with orderly arranged amide groups and benzene rings. As expected, MTHOF‐1 exhibits excellent stability under various conditions and shows clear separation trends for C2H6/C2H4. The IAST selectivity is as high as 2.15 at 298 K. More importantly, dynamic breakthrough experiments have demonstrated that MTHOF‐1 can effectively separate the C2H6/C2H4 feed gas to obtain polymer‐grade C2H4 in one step even under high‐humidity conditions. [ABSTRACT FROM AUTHOR]

Inherent "soft" ionic lattice nature of halide perovskite quantum dots (QDs), triggered by the weak Pb−X (X=Cl, Br, I) bond, is recognized as the primary culprit for their serious instability. A promising way is to construct exceedingly strong ionic interaction inside the QDs and increase their crystal cohesive energy by substituting the interior X− with highly electronegative F−, however, which is challenging and hitherto remains unreported. Here, a "whole‐body" fluorination strategy is proposed for strengthening the interior bonding architecture of QDs, wherein the F− are uniformly distributed throughout the whole nanocrystal encompassing both the interior lattice and surface, successfully stabilizing their "soft" crystal lattice and passivating surface defects. This approach effectively mitigates their intrinsic instability issues including light‐induced phase segregation. As a result, light‐emitting devices based on these QDs exhibit exceptional efficiency and remarkable stability. [ABSTRACT FROM AUTHOR]

Inherent "soft" ionic lattice nature of halide perovskite quantum dots (QDs), triggered by the weak Pb−X (X=Cl, Br, I) bond, is recognized as the primary culprit for their serious instability. A promising way is to construct exceedingly strong ionic interaction inside the QDs and increase their crystal cohesive energy by substituting the interior X− with highly electronegative F−, however, which is challenging and hitherto remains unreported. Here, a "whole‐body" fluorination strategy is proposed for strengthening the interior bonding architecture of QDs, wherein the F− are uniformly distributed throughout the whole nanocrystal encompassing both the interior lattice and surface, successfully stabilizing their "soft" crystal lattice and passivating surface defects. This approach effectively mitigates their intrinsic instability issues including light‐induced phase segregation. As a result, light‐emitting devices based on these QDs exhibit exceptional efficiency and remarkable stability. [ABSTRACT FROM AUTHOR]

Reports on the synthesis and characterization of a polynuclear molybdenum-copper cluster containing a central tetrahedral MoS4 encapsulated by octahedral Cu6 and tetrahedral Cu4 arrays. Monitoring of reaction mechanism by dynamic 95Mo nuclear magnetic resonance (NMR) spectra; X-ray single diffraction analysis.

H2O2 is a widely used eco‐friendly oxidant and a potential energy carrier. Photocatalytic H2O2 production from water and O2 is an ideal approach with the potential to address the current energy crisis and environmental issues. Three zig‐zag two‐dimensional coordination polymers (2D CPs), named CuX‐dptz, were synthesized by a rapid and facile method at room temperature, showing preeminent H2O2 photoproduction performance under pure water and open air without any additives. CuBr‐dptz exhibits a H2O2 production rate high up to 1874 μmol g−1 h−1, exceeding most reported photocatalysts under this condition, even comparable to those supported by sacrificial agents and O2. The coordination environment of Cu can be modulated by halogen atoms (X=Cl, Br, I), which in turn affects the electron transfer process and finally determines the reaction activity. This is the first time that 2D CPs have been used for photocatalytic H2O2 production in such challenging conditions, which provides a new pathway for the development of portable in situ H2O2 photosynthesis devices. [ABSTRACT FROM AUTHOR]

Ultra‐broadband near‐infrared (NIR) phosphor‐converted light‐emitting diodes (pc‐LEDs) have great application prospects in research and industrial fields. However, simultaneously achieving highly efficient and ultra‐broad NIR emission in phosphor material remains a challenge. Herein, an ultra‐broadband NIR emission in the range of 800–1200 nm with ultra‐high emission efficiency of up to 64.2% is first achieved by substituting the Sc3+ site in Cs2NaScCl6 perovskite single‐crystal with a Cr3+ ion. By combining the experimental results with first‐principles calculations, an efficient charge transfer sensitization process from host to Cr3+ is found to be the fundamental reason for the ultra‐high NIR emission efficiency. Benefiting from the excellent efficiency and superior chemical resistance to heat and UV radiation, an ultra‐broadband NIR pc‐LED made of this phosphor demonstrates great potential in biomedical imaging, nondestructive testing, and night‐vision devices. [ABSTRACT FROM AUTHOR]

H2O2 is a widely used eco‐friendly oxidant and a potential energy carrier. Photocatalytic H2O2 production from water and O2 is an ideal approach with the potential to address the current energy crisis and environmental issues. Three zig‐zag two‐dimensional coordination polymers (2D CPs), named CuX‐dptz, were synthesized by a rapid and facile method at room temperature, showing preeminent H2O2 photoproduction performance under pure water and open air without any additives. CuBr‐dptz exhibits a H2O2 production rate high up to 1874 μmol g−1 h−1, exceeding most reported photocatalysts under this condition, even comparable to those supported by sacrificial agents and O2. The coordination environment of Cu can be modulated by halogen atoms (X=Cl, Br, I), which in turn affects the electron transfer process and finally determines the reaction activity. This is the first time that 2D CPs have been used for photocatalytic H2O2 production in such challenging conditions, which provides a new pathway for the development of portable in situ H2O2 photosynthesis devices. [ABSTRACT FROM AUTHOR]

For high‐power white light‐emitting diode devices (WLEDs), phosphor ceramics were widely used because of their high thermal conductivity and temperature resistance. In this study, Y2.998Al5O12: 0.002Ce3+ ceramics were prepared via vacuum reaction sintering and treated by silicon carbide (SiC) abrasives with particle sizes of 8.6, 20, 25, 34, and 50 μm to obtain a single textured surface. The transmittance, reflectance, luminous efficiency (LE) and photoluminescence (PL) intensity of the ceramics were investigated with various surface roughness and different placement. Compared with the double polished (DP) samples, the PL intensity and LE of the single‐surface textured ceramics were greatly improved. It was shown that the roughest ceramics placed with the single polished (SP) side facing the direction of the excitation light (the SP‐forward YAG: Ce ceramics) showed the best performance. [ABSTRACT FROM AUTHOR]

Single-phase aluminum oxynitride (AlON) powders were synthesized by improved direct nitridation (DN). The improved DN method is to obtain high quality powder by adding high nitrogen pressure on the basis of ordinary DN method. Compared with the ordinary DN method, the average particle size of the synthesized powder is reduced by about 20 μm, the morphology tends to be spherical and the sintering activity is higher. Using different particle size α-Al 2 O 3 precursor, a modified DN method was adopted to synthesize spherical, good dispersibility and fine AlON powders. The influence of particle size of raw material α-Al 2 O 3 on sintering properties was investigated. Transparent AlON ceramics with dimensions of φ 103mm × 3 mm with in-line transmittance greater than 80%were fabricated by pressureless sintering from above AlON powders. In addition, the effects of different nitrogen pressure on the morphology, particle size distribution and average particle size of synthetic powder were investigated. On this basis, the differences between DN method and improved DN method on synthetic powder and the possible synthesis mechanism were proposed. [ABSTRACT FROM AUTHOR]

A series of red-emitting (Sr,Ca)AlSiN 3 :Eu2+ phosphor-in-glasses (SCASN PiGs) were successfully prepared by spin coating. The optical, thermal and luminescence performance of the SCASN PiGs with different ratios of phosphor to glass (P1G4, P1G3, P1G2 and P1G1) were investigated systematically. The thermal stabilities of SCASN PiGs are superior to (Sr,Ca)AlSiN 3 :Eu2+ phosphor. As the P1G2 sample was coupled with blue LED chips, warm white light with luminous efficacy (LE) of 115.60 lm/W, color rendering index (CRI) of 73.6 and correlated color temperature (CCT) of 2750 K was achieved running in 100 W COB model. In addition, the CRI of YAG-P1G2 sample was improved to 81.7 when a YAG ceramic was added. These results suggested that the YAG-SCASN PiG is a promising candidate for high CRI and high-power (hp) WLEDs. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) fluorescence imaging poses significant superiority over traditional medical imaging for tumor resection, thus having attracted widely attention. However, for tiny tumor residues, it requires relative high sensitivity to determine. Here, based on persistent luminescence nanoparticles (PLNPs), an ultrasensitive nanoprobe with extraordinary tumor imaging result is developed to guide surgical removal. Persistent luminescence (PersL) is quenched in normal tissue by the outer layer of MnO2, and is recovered due to the degradation of MnO2 in tumor microenvironment, significantly improving the sensitivity of tumor imaging. Combined with the absence of background fluorescence in imaging of PLNPs, ultrahigh sensitivity is achieved. In orthotopic breast cancer model, the intraoperative tumor‐to‐normal tissue (T/NT) signal ratio of the nanoprobe is 58.8, about 9 times that of downconversion nanoparticles. The T/NT ratio of residual tumor (<2 mm) remains 12.4, considerably high to distinguish tumor tissue from normal tissue. Besides, multiple‐microtumor, 4T1 liver‐implanted tumor and lung metastasis models are built to prove that this ultrasensitive nanoprobe is feasible to recognize tumor residues. Notably, PersL imaging takes only 1.5 min, appropriate to be applied for intraoperative imaging. Overall, an ultrasensitive and convenient imaging for recognizing residual tumor tissue is introduced, holding promise for complete surgical removal. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) materials hold great promise as next‐generation efficient emitters due to their theoretical 100% internal quantum efficiency. However, such an intriguing photophysical mechanism is extremely rare in perovskites or their derivatives. Herein, the colloidal synthesis of two‐dimensional CsAgCl2 nanocrystals (NCs) with typical TADF feature is reported first. The TADF mechanism is investigated in detail by combining first‐principles calculations with experimental results, including temperature‐dependent spectral analysis and fs‐transient absorption spectra. A small singlet−triplet state splitting energy (0.082 eV) and a large spatial separation of charge density |Ψ|2 of valence band maximum and conduction band minimum are observed, which are prerequisites for TADF. Moreover, these CsAgCl2 NCs deliver an ultralow X‐ray detection limit of 170.5 nGyair s−1 and a high imaging resolution of 11.5 lp mm−1, much superior to the commercial scintillators. [ABSTRACT FROM AUTHOR]

Zero‐dimensional (0D) copper‐based perovskite‐derivative nano‐scintillators (NSs), as a promising non‐toxic alternative to lead‐based halide perovskite, have shown great potential in flexible X‐ray detection and imaging. However, their practical applications are still impeded by low X‐ray imaging resolution associated with inadequate radioluminescence (RL) and poor environmental stability. Herein, for the first time a simple but valid Mn2+‐activation strategy is proposed to highly enhance the RL and stability of 0D Cs3Cu2I5 NSs, where the Mn2+ ions are embedded into the highly localized [Cu2I5]3− units by utilizing a modified hot‐injection method. As such, a newly emerged emission band of Mn2+ ion centered at ≈562 nm coupled with much improved intrinsic self‐trapped excitons (STE) emission of the 0D Cs3Cu2I5 host peaking at ≈445 nm can be achieved in these resultant Mn2+‐activated 0D Cs3Cu2I5 NSs, thereby delivering a light yield of 71 000 photons MeV−1 that is much superior to their lead‐based perovskite counterparts and commercial scintillators. As a consequence, X‐ray detectors made of these Mn2+‐activated NSs implement an ultrahigh X‐ray imaging resolution of 16.2 line pairs mm−1 and an ultra‐low detection limit of 127.5 nGyair s−1, highlighting their potential as promising candidates for flexible X‐ray detection and imaging. [ABSTRACT FROM AUTHOR]

Exciton localization is an approach for preparing highly luminescent semiconductors. However, realizing strongly localized excitonic recombination in low‐dimensional materials such as two‐dimensional (2D) perovskites remains challenging. Herein, we first propose a simple and efficient Sn2+ vacancy (VSn) tuning strategy to enhance excitonic localization in 2D (OA)2SnI4 (OA=octylammonium) perovskite nanosheets (PNSs), increasing their photoluminescence quantum yield (PLQY) to ≈64 %, which is among the highest values reported for tin iodide perovskites. Combining experimental with first‐principles calculation results, we confirm that the significantly increased PLQY of (OA)2SnI4 PNSs is primarily due to self‐trapped excitons with highly localized energy states induced by VSn. Moreover, this universal strategy can be applied for improving other 2D Sn‐based perovskites, thereby paving a new way to fabricate diverse 2D lead‐free perovskites with desirable PL properties. [ABSTRACT FROM AUTHOR]

Exciton localization is an approach for preparing highly luminescent semiconductors. However, realizing strongly localized excitonic recombination in low‐dimensional materials such as two‐dimensional (2D) perovskites remains challenging. Herein, we first propose a simple and efficient Sn2+ vacancy (VSn) tuning strategy to enhance excitonic localization in 2D (OA)2SnI4 (OA=octylammonium) perovskite nanosheets (PNSs), increasing their photoluminescence quantum yield (PLQY) to ≈64 %, which is among the highest values reported for tin iodide perovskites. Combining experimental with first‐principles calculation results, we confirm that the significantly increased PLQY of (OA)2SnI4 PNSs is primarily due to self‐trapped excitons with highly localized energy states induced by VSn. Moreover, this universal strategy can be applied for improving other 2D Sn‐based perovskites, thereby paving a new way to fabricate diverse 2D lead‐free perovskites with desirable PL properties. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskites carry unique semiconducting properties and advanced flexible crystal structures. These characteristics of organic–inorganic hybrid perovskites create a promising candidacy for circularly polarized light (CPL) detection. However, CPL detections based on chiral perovskites are limited to UV and visible wavelengths. The natural quantum well structures of layered hybrid perovskites generate strong light–matter interactions. This makes it possible to achieve near‐infrared (NIR) CPL detection via two‐photon absorption in the sub‐wavelength region. In this study, cooperative strategies of dimension increase and mixed spacer cations are used to obtain a pair of chiral multilayered perovskites (R‐β‐MPA)EA2Pb2Br7 and (S‐β‐MPA)EA2Pb2Br7 (MPA = methylphenethylammonium and EA = ethylammonium). The distinctive bi‐cations interlayer and multilayered inorganic skeletons provide enhanced photoconduction. Moreover, superior photoconduction leads to the prominent NIR CPL response with a responsivity up to 8.1 × 10−5 A W−1. It is anticipated that this work can serve as a benchmark for the fabrication and optimization of efficient NIR CPL detection by simple chemical design. [ABSTRACT FROM AUTHOR]

Developing practical storage technologies for acetylene (C2H2) is important but challenging because C2H2 is useful but explosive. Here, a novel metal–organic framework (MOF) (FJI‐H36) with adaptive channels was prepared. It can effectively capture C2H2 (159.9 cm3 cm−3) at 1 atm and 298 K, possessing a record‐high storage density (561 g L−1) but a very low adsorption enthalpy (28 kJ mol−1) among all the reported MOFs. Structural analyses show that such excellent adsorption performance comes from the synergism of active sites, flexible framework, and matched pores; where the adsorbed‐C2H2 can drive FJI‐H36 to undergo induced‐fit transformations step by step, including deformation/reconstruction of channels, contraction of pores, and transformation of active sites, finally leading to dense packing of C2H2. Moreover, FJI‐H36 has excellent chemical stability and recyclability, and can be prepared on a large scale, enabling it as a practical adsorbent for C2H2. This will provide a useful strategy for developing practical and efficient adsorbents for C2H2 storage. [ABSTRACT FROM AUTHOR]

Developing practical storage technologies for acetylene (C2H2) is important but challenging because C2H2 is useful but explosive. Here, a novel metal–organic framework (MOF) (FJI‐H36) with adaptive channels was prepared. It can effectively capture C2H2 (159.9 cm3 cm−3) at 1 atm and 298 K, possessing a record‐high storage density (561 g L−1) but a very low adsorption enthalpy (28 kJ mol−1) among all the reported MOFs. Structural analyses show that such excellent adsorption performance comes from the synergism of active sites, flexible framework, and matched pores; where the adsorbed‐C2H2 can drive FJI‐H36 to undergo induced‐fit transformations step by step, including deformation/reconstruction of channels, contraction of pores, and transformation of active sites, finally leading to dense packing of C2H2. Moreover, FJI‐H36 has excellent chemical stability and recyclability, and can be prepared on a large scale, enabling it as a practical adsorbent for C2H2. This will provide a useful strategy for developing practical and efficient adsorbents for C2H2 storage. [ABSTRACT FROM AUTHOR]

Porous supramolecular assemblies constructed by noncovalent interactions are promising for adsorptive purification of methane because of their easy regeneration. However, the poor stability arising from the weak noncovalent interactions has obstructed their practical applications. Here, we report a robust and easily regenerated polyhedron‐based cationic framework assembled from a metal–organic square. This material exhibits a very low affinity for CH4 and N2, but captures other competing gases (e.g. C2H6, C3H8, and CO2) with a moderate affinity. These results underpin highly selective separation of a range of gas mixtures that are relevant to natural gas and industrial off‐gas. Dynamic breakthrough studies demonstrate its practical separation for C2H6/CH4, C3H8/CH4, CO2/N2, and CO2/CH4. Particularly, the separation time is ≈11 min g−1 for the C2H6/CH4 (15/85 v/v) mixture and ≈49 min g−1 for the C3H8/CH4 (15/85 v/v) mixture (under a flow of 2.0 mL min−1), respectively, enabling its capability for CH4 purification from light alkanes. [ABSTRACT FROM AUTHOR]

Porous supramolecular assemblies constructed by noncovalent interactions are promising for adsorptive purification of methane because of their easy regeneration. However, the poor stability arising from the weak noncovalent interactions has obstructed their practical applications. Here, we report a robust and easily regenerated polyhedron‐based cationic framework assembled from a metal–organic square. This material exhibits a very low affinity for CH4 and N2, but captures other competing gases (e.g. C2H6, C3H8, and CO2) with a moderate affinity. These results underpin highly selective separation of a range of gas mixtures that are relevant to natural gas and industrial off‐gas. Dynamic breakthrough studies demonstrate its practical separation for C2H6/CH4, C3H8/CH4, CO2/N2, and CO2/CH4. Particularly, the separation time is ≈11 min g−1 for the C2H6/CH4 (15/85 v/v) mixture and ≈49 min g−1 for the C3H8/CH4 (15/85 v/v) mixture (under a flow of 2.0 mL min−1), respectively, enabling its capability for CH4 purification from light alkanes. [ABSTRACT FROM AUTHOR]

Catalysis, Co-Encapsulation, Combinatorial Self-Assembly, Coordination Cages, Host-Guest Systems The controllable arrangement of different ligands not only gives rise to a family of six different palladium-organic cages with systematically varied shapes and cavities, but also leads to emergent host-guest chemistry of the heteroleptic cages due to the fusion of two half cavities from their parent homoleptic cages. Inside Back Cover: Combinatorial Self-Assembly of Coordination Cages with Systematically Fine-Tuned Cavities for Efficient Co-Encapsulation and Catalysis (Angew. [Extracted from the article]

Keywords: Catalysis; Co-Encapsulation; Combinatorial Self-Assembly; Coordination Cages; Host-Guest Systems EN Catalysis Co-Encapsulation Combinatorial Self-Assembly Coordination Cages Host-Guest Systems 1 1 1 08/11/22 20220815 NES 220815 B Ein kombinatorischer Ansatz b für die Selbstorganisation von enPd(NO SB 3 sb ) SB 2 sb mit drei verschiedenen Liganden wird im Forschungsartikel (e202204732) von Li-Xuan Cai, Qihui Chen, Qing-Fu Sun und Mitarbeitern vorgestellt. Catalysis, Co-Encapsulation, Combinatorial Self-Assembly, Coordination Cages, Host-Guest Systems Innenrücktitelbild: Combinatorial Self-Assembly of Coordination Cages with Systematically Fine-Tuned Cavities for Efficient Co-Encapsulation and Catalysis (Angew. [Extracted from the article]

Antiperovskites have been studied since the 1980s because of their rich physical and chemical properties, but their linear and second‐order nonlinear optical responses remain largely unknown. Here we report a new polar crystal, Cs3Cl(HC3N3S3) (I), which features a quasi‐one‐dimensional antiperovskite structure composed of ClCs6 polyhedra and A‐site [HC3N3S3]2− rings. To our best knowledge, this kind of antiperovskite structure is reported for the first time. Remarkably, I exhibits a very strong nonlinear optical response up to 11.4 times that of the benchmark KH2PO4 and exceptionally large birefringence of 0.52. The first‐principles calculations and structural analyses reveal that [HC3N3S3]2− is the "material gene" while the antiperovskite structural feature making it in a favorable arrangement. This work provides a new structural platform for the rational design of integrated optoelectronic materials with linear and second‐order nonlinear optical responses. [ABSTRACT FROM AUTHOR]

Because C2H4 plays an essential role in the chemical industry, economical and energy‐efficient separation of ethylene (C2H4) from ethane (C2H6) is extremely important. With the exception of energy‐intensive cryogenic distillation, there are few one‐step methods to obtain polymer‐grade (≥99.95 % pure) C2H4 from C2H4/C2H6 mixtures. Here we report a highly stable metal‐organic‐framework (MOF) FJI‐H11‐Me(des) (FJI‐H=Hong's group in Fujian Institute of Research on the Structure of Matter) which features one‐dimensional hexagonal nonpolar pore surfaces constructed by aromatic rings and alkyl groups. This FJI‐H11‐Me(des) adsorbs C2H6 rather than C2H4 between 273 and 303 K. Practical breakthrough experiments with C2H4 containing 1 % C2H6 have shown that FJI‐H11‐Me(des) can realize the acquisition in one‐step of polymer‐grade, 99.95 % pure C2H4 under various conditions including different gas flow rates, temperatures and relative humidity. [ABSTRACT FROM AUTHOR]

Antiperovskites have been studied since the 1980s because of their rich physical and chemical properties, but their linear and second‐order nonlinear optical responses remain largely unknown. Here we report a new polar crystal, Cs3Cl(HC3N3S3) (I), which features a quasi‐one‐dimensional antiperovskite structure composed of ClCs6 polyhedra and A‐site [HC3N3S3]2− rings. To our best knowledge, this kind of antiperovskite structure is reported for the first time. Remarkably, I exhibits a very strong nonlinear optical response up to 11.4 times that of the benchmark KH2PO4 and exceptionally large birefringence of 0.52. The first‐principles calculations and structural analyses reveal that [HC3N3S3]2− is the "material gene" while the antiperovskite structural feature making it in a favorable arrangement. This work provides a new structural platform for the rational design of integrated optoelectronic materials with linear and second‐order nonlinear optical responses. [ABSTRACT FROM AUTHOR]

Because C2H4 plays an essential role in the chemical industry, economical and energy‐efficient separation of ethylene (C2H4) from ethane (C2H6) is extremely important. With the exception of energy‐intensive cryogenic distillation, there are few one‐step methods to obtain polymer‐grade (≥99.95 % pure) C2H4 from C2H4/C2H6 mixtures. Here we report a highly stable metal‐organic‐framework (MOF) FJI‐H11‐Me(des) (FJI‐H=Hong's group in Fujian Institute of Research on the Structure of Matter) which features one‐dimensional hexagonal nonpolar pore surfaces constructed by aromatic rings and alkyl groups. This FJI‐H11‐Me(des) adsorbs C2H6 rather than C2H4 between 273 and 303 K. Practical breakthrough experiments with C2H4 containing 1 % C2H6 have shown that FJI‐H11‐Me(des) can realize the acquisition in one‐step of polymer‐grade, 99.95 % pure C2H4 under various conditions including different gas flow rates, temperatures and relative humidity. [ABSTRACT FROM AUTHOR]

Birefringent materials are highly demanded for high‐performance polarized optics. As compared with artificial anisotropic metamaterials, anisotropic crystals have advantages of low optical losses and easy processing, but their birefringence is still limited. Herein, based on first‐principles studies, we identified a new type of functional anion units, (HxC6N9)(3−x)− (x=0, 1, 2), and then successfully synthesized a new anisotropic crystal, namely, CsH2C6N9⋅H2O (I), whose crystal structure consists of (H2C6N9)− anions. Remarkably, I is ultraviolet transparent and exhibits very large birefringence of about 0.55@550 nm, which is much larger than those of commercial birefringent crystals. These results make I a candidate for highly efficient manipulation of optics and light in optical modulation devices. Theoretical calculations reveal that large birefringence mainly arises from the cooperative π orbitals in (H2C6N9)− anions. This work provides a new insight on the underlying structure–property relationships of anisotropic crystals. [ABSTRACT FROM AUTHOR]

Birefringent materials are highly demanded for high‐performance polarized optics. As compared with artificial anisotropic metamaterials, anisotropic crystals have advantages of low optical losses and easy processing, but their birefringence is still limited. Herein, based on first‐principles studies, we identified a new type of functional anion units, (HxC6N9)(3−x)− (x=0, 1, 2), and then successfully synthesized a new anisotropic crystal, namely, CsH2C6N9⋅H2O (I), whose crystal structure consists of (H2C6N9)− anions. Remarkably, I is ultraviolet transparent and exhibits very large birefringence of about 0.55@550 nm, which is much larger than those of commercial birefringent crystals. These results make I a candidate for highly efficient manipulation of optics and light in optical modulation devices. Theoretical calculations reveal that large birefringence mainly arises from the cooperative π orbitals in (H2C6N9)− anions. This work provides a new insight on the underlying structure–property relationships of anisotropic crystals. [ABSTRACT FROM AUTHOR]

Chiral hybrid perovskites are recently considered for circularly polarized light (CPL) detection owing to the integration of chiral activity and prominent photoelectric characteristics. However, chiral hybrid perovskites are limited because of the restricted chiral cations; efficient self‐driven CPL detection without external power sources required for halide perovskite photodetectors is desirable but remains scarce. Herein, two alternating cations in the interlayer space of chiral‐polar hybrid perovskites, (R‐β‐MPA)EAPbBr4 and (S‐β‐MPA)EAPbBr4 (MPA = methylphenethylammonium and EA = ethylammonium), are developed via a mixed‐cation approach. These perovskites exhibit chiral characteristics featuring CPL detection with high detectivity. Notably, the chiral‐polar structure gives rise to a built‐in electric field to realize self‐driven CPL detection without an applied voltage, and the photocurrent difference reaches 19% under the right and left CPL irradiation. Moreover, a prominent response time of 300 µs is obtained, which is among the fastest for CPL detection. This work highlights the significance of chemical design in the exploration of new chiral perovskites, which will broaden the scope of chiral materials for high‐performance applications. [ABSTRACT FROM AUTHOR]

The realization of high color rendering index (CRI) is still a great challenge for high‐power LEDs (hp‐LEDs), which is hindered by the phosphor converter. In this work, based on the strategy of Ce3+ and Mn2+ multi‐ion substitution, the single‐structured LuAG:Ce,Mn ceramics with high CRI were prepared via regulating the ratio of tri‐color (red, green, and blue) components. The effects of Mn2+‐Si4+ pairs doping content on the crystal structure, morphologies, and luminescence properties were investigated in detail. The red emission centered at 590 and 750 nm were effectively compensated by regulating Mn2+ occupancy sites, resulting in a significant improvement of CRI. Pure white light with general CRI Ra up to 91.0, special CRI R9 reaching 37.9 and LE as high as 85.07 lm/W was achieved, when the hp‐LEDs were constructed from related phosphor ceramic Ce02Mn7. These results suggest that the LuAG:Ce,Mn phosphor ceramics are highly promising color converters for hp‐LEDs application. [ABSTRACT FROM AUTHOR]