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Metal halide perovskite ferroelectrics combining spontaneous polarization and excellent semiconducting properties is an ideal platform for enabling self‐driven X‐ray detection. However, achievements to date have been only based on uniaxiality, which increases the complexity of device fabrication. Multi‐axial ferroelectric materials have multiple equivalent polarization directions, making them potentially amenable to multi‐axial self‐driven X‐ray detection, but the report on these types of materials is still a huge blank. Herein, a high‐quality (BA)2(EA)2Pb3I10 (1) biaxial ferroelectric single crystal was successfully grown, which exhibited significant spontaneous polarization along the c‐axis and b‐axis. Under X‐ray irradiation, bulk photovoltaic effect (BPVE) was exhibited along both the c‐axis and b‐axis, with open circuit voltages (Voc) of 0.23 V and 0.22 V, respectively. Then, the BPVE revealed along the inversion of polarized direction with the polarized electric fields. Intriguingly, due to the BPVE of 1, 1 achieved multi‐axial self‐driven X‐ray detection for the first time (c‐axis and b‐axis) with relatively high sensitivities and ultralow detection limits (17.2 nGyair s−1 and 19.4 nGyair s−1, respectively). This work provides a reference for the subsequent use of multi‐axial ferroelectricity for multi‐axial self‐driven optoelectronic detection. [ABSTRACT FROM AUTHOR]

Photopyroelectric‐based circularly polarized light (CPL) detection, coupling the pyro‐phototronic effect and chiroptical phenomena, has provided a promising platform for high‐performance CPL detectors. However, as a novel detection strategy, photopyroelectric‐based CPL detection is currently restricted by the short‐wave optical response, underscoring the urgent need to extend its response range. Herein, visible‐to‐near‐infrared CPL detection induced by the pyro‐phototronic effect is first realized in chiral‐polar perovskites. Specifically, chiral‐polar multilayered perovskites (S‐BPEA)2FAPb2I7 (1‐S, S‐BPEA = (S)‐1‐4‐Bromophenylethylammonium, FA = formamidinium) with spontaneous polarization shows intrinsic pyroelectric and photopyroelectric performance. Strikingly, combining its merits of the pyro‐phototronic effect and intrinsic wide‐spectrum spin‐selective effect, chiral multilayered 1‐S presents efficient photopyroelectric‐based broadband CPL detection performance spanning 405–785 nm. This research first realizes photopyroelectric‐based infrared CPL detection and also sheds light on developing high‐performance broadband CPL detectors based on the pyro‐phototronic effect in the fields of optics, optoelectronics, and spintronics. [ABSTRACT FROM AUTHOR]

2D hybrid perovskites, with their high X‐ray absorption and extended carrier transport, present excellent promise for efficient direct X‐ray detection. However, most of the current devices require external bias voltage, which results in the need for significant energy consumption and severe ion migration, therefore, it is urgent to develop new types of materials for achieving efficient passive X‐ray detection. Herein, two novel chiral polar alternating cations intercalation (ACI)‐type hybrid perovskite materials, named (R/S‐PPA)(IEA)PbBr4 (1‐R/S, (R/S)‐PPA = R/S‐1‐phenylpropylamine; IEA = iodoethylamine), are constructed by integrating the chiral aromatic spacer R/S‐PPA and the iodine‐substituted spacer IEA. Various intermolecular interactions, such as I···I, C─H···I, π···π interactions, are introduced due to the introduction of I‐substituted chain amines, which effectively suppresses ion migration and thus lead to improved operational stability. The device constructed along the polar axis displays superior X‐ray detection performance, such as relatively high sensitivity and an ultra‐low limit of detection (LoD) of 3.0 nGy s−1, making it the first chiral ACI‐type perovskite material for realizing efficient passive X‐ray detection. Furthermore, 1‐R also presents low dark current drift and exceptional irradiation stability. This work provides new thought for using novel ACI‐type polar perovskite for high‐performance passive direct X‐ray detection. [ABSTRACT FROM AUTHOR]

Circularly polarized light (CPL) detection has wide applications in many fields, where the anisotropy factor (gIph) is an important indicator to characterize the CPL detection performance. So far, many materials with high gIph have been reported, however, the exploration of the regulation of gIph is still in its infancy. Herein, two novel alternating chiral‐achiral cations intercalation‐type chiral hybrid perovskites (CHPs), named (R/S‐1‐phenylpropylamine)(propylamine)PbBr4 (1‐R/S), exhibit above room‐temperature (RT) polar‐phase transition, which greatly regulates the gIph value. The gIph of 1‐R is 0.04 in high‐temperature phase chiral non‐polar (P212121) by applying 5 V bias, interestingly, with the temperature decrease, the gIph value in low‐temperature phase chiral polar (P21) gradually increases (0.22@360K, 0.40@340K, 0.47@320K), and finally reaches a maximum of 0.5 at RT. Such value is not only the highest among 2D CHPs to date, but presents a 12.5‐fold amplification compared with 0.04. Further, this rare phenomenon should be attributed to the built‐in electric field induced by the polar photovoltaic effect, which sheds light on further obtaining CHPs with large gIph. [ABSTRACT FROM AUTHOR]

2D chiral hybrid perovskites have recently emerged as outstanding semiconductor materials. However, most of the reported 2D chiral perovskites have limited structural types and contain high levels of toxic lead, which severely hinders their further applications. Herein, by using a mixed‐cation strategy, an unprecedented type of lead‐free cluster‐based 2D chiral hybrid double perovskite derivatives are successfully obtained, [(R/S‐PPA)4(IPA)6Ag2Bi4I24]·2H2O (1‐R and 1‐S), and [(R/S‐PPA)4(n‐BA)6Ag2Bi4I24]·2H2O (2‐R and 2‐S) (R/S‐PPA=R/S–1‐phenylpropylamine; IPA=isopentylamine; n‐BA=n‐butylamine). Their inorganic skeletons are linked by binuclear {Bi2I10} and infinite chain {Ag2Bi2I14}∞, in which bismuth clusters and multiple coordination modes (e.g., tetrahedral AgI4 and octahedral AgI6) are introduced into the double perovskite system for the first time. This introduction induces distortion of the inorganic layer, which may facilitate the transfer of chirality from the chiral cations into achiral double perovskite skeletons. Further, circular dichroism measurements and circularly polarized light detection confirm their inherent chiral optical activities. In addition, 1‐S exhibits an ultralow X‐ray detection limit of 129.5 nGy s−1, which is 42‐fold lower than that of demands in regular medical diagnosis (5.5 µGy s−1). This study provides a pathway to construct novel type of lead‐free cluster‐based double perovskite derivatives. [ABSTRACT FROM AUTHOR]

The exceptional photophysical properties of 3D organic–inorganic lead halide hybrids (OILHs) endow their significant potential for usage in optoelectronics, which has sparked intense research on novel 3D OILHs and associated applications. However, constructing new 3D OILHs based on large organic cations suffers from tough challenges due to the limitation of the Goldschmidt tolerance factor rule, let alone further explorations of their practical applications. Herein, a brand‐new 3D lead chloride hybrid, (1MPZ)Pb4Cl10·H2O (1, 1MPZ = 1‐methylpiperazine) is reported, featuring a dense 3D lead chloride framework made of the corner‐, edge‐, and face‐shared lead chloride polyhedra. 1 presents a broadband white light emission with a large Stokes shift and a nanosecond photoluminescence lifetime, which originates from radiative recombination of self‐trapped excitons (STEs) induced by the highly distorted structure. Such a reabsorption‐free and fast‐decayed STEs emission coupling with the dense 3D architecture further enables 1 with effective X‐ray scintillation with good sensitivity. Impressively, 1 also shows superior environmental and radiation stability. This study provides a new 3D OILH with appealing luminescence, not only expanding the 3D OILH family but also inspiring the exploitation of their optoelectronic applications. [ABSTRACT FROM AUTHOR]

Cup‐shaped molecules are of great interest due to their appealing architectures and properties. Compared with widely studied calixarenes, polyoxometalate‐based cup‐shaped molecules currently remain a virgin land waiting for exploration. In this work, we report the first discovery of two giant cup‐shaped inorganic–organic hybrid polyoxoniobates (PONbs) of {Cu12Nb120} and {Cd16Nb128}. The former integrates three tricyclic Nb24 clusters and a hexacyclic Nb48 cluster into a cup‐shaped molecule via a Cu12 metallacalixarene, while the latter unifies two tricyclic Nb24 clusters and a brand‐new pentacyclic Nb40 cluster into another cup‐shaped molecule via a hybrid Cd16 unit. With 132 and 144 metal centers, {Cu12Nb120} and {Cd16Nb128} show the largest two inorganic–organic hybrid PONbs known to date. [ABSTRACT FROM AUTHOR]

Nanoscale {Nb68O200} cages have been successfully employed as flexible and stable secondary building units to combine with bridging copper–amine complexes to construct two proton conductive polyoxoniobate frameworks, demonstrating a promising strategy for making new porous materials. [ABSTRACT FROM AUTHOR]

In this work, two rare high‐dimensional polyoxoniobates with formulas of H9[Cu(en)(H2O)2][Cu(en)2]8[Dy(H2O)4]3[Nb24‐O69(H2O)3]2 ⋅ 36H2O (1) and H9K[Cu(en)2(H2O)]5[Cu(en)2]4‐[Eu(H2O)4]3[Nb24O69(H2O)3]2 ⋅ 2en ⋅ 45H2O (2) have been obtained under hydrothermal conditions. These extended materials are constructed from lanthanide‐incorporated triangular‐prism‐like polyoxoniobate secondary building units (SBUs) {[Ln(H2O)4]3[Nb24O69(H2O)3]2} (Ln=Dy, Eu). 1 and 2 represent the first examples of high‐dimensional polyoxometalate materials based on such lanthanide‐incorporated triangular‐prism‐like polyoxoniobate SBUs. Furthermore, the proton conduction property and the luminescent emission of these materials were evaluated. [ABSTRACT FROM AUTHOR]

A series containing the highest nuclearity polyoxoniobate (PONb) nanoclusters, ranging from dimers to tetramers, has been obtained. They include one 114-nuclear {Li8⊂Nb114O316}, one 81-nuclear {Li3K⊂Nb81O225}, and one 52-nuclear {H4Nb52O150}. The Nb nuclearity of these PONbs is remarkably larger than those of all known high-nuclearity PONbs (≤32). Furthermore, the introduction of 3d Cu2+ ions can lead to the generation of extended inorganic-organic hybrid frameworks built from novel, high-nuclearity, nanoscale heterometallic PONb building blocks {H3Cu3Nb78O222} or {H3Cu4(en)Nb78O222}. These building blocks also contain the largest number of Nb centers of any heterometallic PONbs reported to date. The synthesis of new-type PONbs has long been a challenging subject in PONb chemistry. [ABSTRACT FROM AUTHOR]