A series containing the highest nuclearity polyoxoniobate (PONb) nanoclusters, ranging from dimers to tetramers, has been obtained. They include one 114-nuclear {Li ⊂Nb O }, one 81-nuclear {Li K⊂Nb O }, and one 52-nuclear {H Nb O }. The Nb nuclearity of these PONbs is remarkably larger than those of all known high-nuclearity PONbs (≤32). Furthermore, the introduction of 3d Cu ions can lead to the generation of extended inorganic-organic hybrid frameworks built from novel, high-nuclearity, nanoscale heterometallic PONb building blocks {H Cu Nb O } or {H Cu (en)Nb O }. 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.

The combination of polyoxoniobates (PONbs) with 3d metal ions, azoles, and organoamines is a general synthetic procedure for making unprecedented PONb metal complex cage materials, including discrete molecular cages and extended cage frameworks. By this method, the first two PONb metal complex cages K4@{[Cu29(OH)7(H2O)2(en)8(trz)21][Nb24O67(OH)2(H2O)3]4} and [Cu(en)2]@{[Cu2(en)2(trz)2]6(Nb68O188)} have been made. The former exhibits a huge tetrahedral cage with more than 120 metal centers, which is the largest inorganic–organic hybrid PONb known to date. The later shows a large cubic cage, which can act as building blocks for cage‐based extended assembly to form a 3D cage framework {[Cu(en)2]@{[Cu2(trz)2(en)2]6[H10Nb68O188]}}. These materials exhibit visible‐light‐driven photocatalytic H2 evolution activity and high vapor adsorption capacity. The results hold promise for developing both novel cage materials and largely unexplored inorganic–organic hybrid PONb chemistry.

Lead-free halide double perovskites (HDPs) have sparked broad interest in developing “green” photodetectors; however, self-powered X-ray detectors in this family remain elusive. Here, by exploiting the chirality-induced polar photovoltaic effect in a chiral-polar 2D HDP, (R-MPA)4AgBiI8 (1, R-MPA = R-β-methylphenethylammonium), we successfully realized self-powered X-ray detection. The significant spontaneous electric polarization in 1 gives it a large polar photovoltage of 0.36 V, which drives the separation and transport of X-ray-generated carriers, thus acquiring the capability of self-powered detection. Consequently, X-ray detectors based on high-quality single crystals of 1 exhibit a high sensitivity of 46.3 μC Gy–1 cm–2 and an ultralow detection limit of 85 nGy s–1 at zero bias. The sensitivity can be further increased to 949.6 μC Gy–1 cm–2 at 50 V bias, outperforming all current 2D HDP detectors. Our work is the first to demonstrate self-powered X-ray detection in single-phase lead-free HDPs, enlightening future design of “green” self-powered radiation detectors.

Lead halide perovskites have made great advance in direct X‐ray detection, however the presence of toxic lead and the requirement of high working voltages severely limit their applicability and operational stability. Thus, exploring “green” lead‐free hybrid perovskites capable of detecting X‐rays at zero bias is crucial but remains toughly challenging. Here, utilizing chiral R/S‐1‐phenylpropylamine (R/S‐PPA) cations, a pair of 0D chiral‐polar perovskites, (R/S‐PPA)2BiI5 (1R/1S) are constructed. Their intrinsic spontaneous electric polarization induces a large bulk photovoltage of 0.63 V, which acts as a driving force to separate and transport photogenerated carriers, thus endowing them with the capability of self‐driven detection. Consequently, self‐driven X‐ray detectors with a low detection limit of 270 nGy s−1 are successfully constructed based on high‐quality, inch‐sized single crystals of 1R. Notably, they show suppressed baseline drift under the self‐driven mode, exhibiting superior operational stability. This study realizes self‐driven X‐ray detection in a single‐phase lead‐free hybrid perovskite by exploiting the intrinsic bulk photovoltaic effect, which sheds light on future explorations of lead‐free hybrid perovskites toward “green” self‐driven radiation detectors with high performance.

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 promissing...

A rare 3D porous chiral polyoxoniobate framework, [Cu(en)2(H2O)]2{[Cu(en)]4[Cu(en)2]5 {[Cu(en)2KNb24O72H10]2}.6en.70H2O(1) (en=ethylenediamine) based on two types of isomeric {Cu(en)2KNb24O72H10} clusters (α-CuKNb24 and β-CuKNb24) has been synthesized by hydrothermal reaction. Interestingly, the α-CuKNb24...

Cup-shaped molecules are of great interest due to their appealing architectures and properties. Compared with widely studied calixarenes, polyoxometalate-based cupshaped 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 {Cu 12 Nb 120 } and {Cd 16 Nb 128 }. The former integrates three tricyclic Nb 24 clusters and a hexacyclic Nb 48 cluster into a cup-shaped molecule via a Cu 12 metallacalixarene, while the latter unifies two tricyclic Nb 24 clusters and a brandnew pentacyclic Nb 40 cluster into another cup-shaped molecule via a hybrid Cd 16 unit. With 132 and 144 metal centers, {Cu 12 Nb 120 } and {Cd 16 Nb 128 } show the largest two inorganicorganic hybrid PONbs known to date.

Two new extended polyoxometalate (POM) architectures based on lanthanide-incorporated polyoxoniobate (Ln-incorporated PONb) cages, namely, H4[CuII(en)2]4{K4(H2O)2­[CuII(en)2]5[CuII 5­​(trz)2(en)4(OH)2]­[Dy2CuII 2­(en)2(CO3)3­(H2O)2(OH)3]­[Dy­(H2O)4]­[Dy­Nb23O68­(H2O)4]2}·60H2O (1, en = ethylenediamine) and H20[CuII(en)2]4­{[CuII(en)2]4­[Dy2(C2O4)­(H2O)4]2­[(Nb32(OH)4­(H2O)3­O89]2}·54H2O (2), have been successfully synthesized and structurally characterized, demonstrating a feasible strategy to develop functional POM materials. In addition, the proton conductivity and magnetic behaviors of both 1 and 2 were studied.