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The synthesis of zirconium MOFs with zeolite net is quite challenging due to the high connectivity of Zr6 clusters, which is far from tetrahedral connection, a requisite for zeolite net. In this work, we demonstrate a six‐membered ring (6MR) strategy through mimicking of mineral zeolites with mixed ditopic and tritopic carboxylate linkers. With this strategy, the ditopic linker cross‐links Zr6 clusters to form 4‐connected zeolite‐like nets, while the tritopic one is used to direct the formation of 6MR and simultaneously consumes extra coordination sites on the cluster. The feasibility of this strategy is shown by one zeolitic metal–organic framework (NNM‐5) and this strategy has also led to the synthesis of the other dia‐type zirconium MOF (NNM‐6). Interestingly, as the tritopic linker not only directs the formation of 6MR but also partitions 6MR into small segments, NNM‐5 with SOD topology shows a structural feature of small aperture and big cage, which has led to efficient separation of hexane isomers. With both exceptionally high n‐hexane uptake (65.9 cm3 g−1) and size‐exclusion selectivity, an exceptional separation capability is verified by breakthrough experiments. Calculation results demonstrate that the large difference of diffusion energy barrier due to the small aperture accounts for the underlying separation mechanism. [ABSTRACT FROM AUTHOR]

Herein, we show two cases of pillar-layered MOFs which are built solely with one kind of three-dimensional (3D) ditopic ligand. The ligand in both structures functions not only as an intralayer linker in the layer but also as a "pillar" between adjacent layers. Such multi-functionality of the linker is accompanied by uncommon asymmetric 10-c metal hexamer or 7-c tetramer nodes, which have never been reported in previous 3D MOF structures. [ABSTRACT FROM AUTHOR]

We report hierarchical CoSx/Ni(OH)2/NF heterostructure nanorod arrays, which manifest superior bifunctional catalytic activities for the HER and UOR due to amorphous Ni(OH)2, synergistic effect of multiple components and self-supported structure. The CoSx/Ni(OH)2/NF-based urea electrolyzer requires a low cell voltage of 1.485 V to deliver 10 mA cm−2, which is obviously lower than that needed in water electrolysis. [ABSTRACT FROM AUTHOR]

The construction of cluster-based crystalline chalcogenide structures through the traditional solvothermal method relies on synergistic control of precursors, template cations and auxiliary solvents. Generally, the combination of metal precursors plays a crucial role in controlling the size of clusters, while organic templates and auxiliary solvents usually contribute to the type of clusters and architecture of the framework. Decades of synthetic efforts have been mainly devoted to expanding organic amine templates for constructing new structures. However, the important role of auxiliary solvents in enriching the chalcogenide family is usually disregarded. Reported here are several new crystalline In–Se compounds (ISP-1 to 4) with different dimensions, obtained by elaborately regulating auxiliary solvents under the direction of the same organic template, piperidine. Of these four structures, ISP-1 is constructed by irregular supertetrahedral clusters, giving a novel 2D structure with a corner-shared single Se atom and In2Se3 five-member ring as linkers; ISP-2 has a 1D structure composed by interlinked In2Se3 five-member rings; ISP-4 is constructed by supertetrahedral T2 clusters exhibiting an uncommon zeolite-like mog network. [ABSTRACT FROM AUTHOR]

The first incorporation of the 1,2,4-triazolate ligand into metal-chalcogenide semiconductor frameworks resulted in the formation of two new supertetrahedral-cluster-based triazolate frameworks (SCTFs) with hybrid inter-cluster connection modes, namely, SCTF-1 with an inorganic/organic linker ratio of 3 : 1 and SCTF-2 with a linker ratio of 2 : 2. The optical properties of these two close models were investigated. [ABSTRACT FROM AUTHOR]

Enlarging the openess of chalcogenide frameworks is of significance for functionalizing semiconducting open frameworks, which are usually limited by their own interpenetration due to the rigid clusters and monotonous linkers. Herein, we report two zeolite-like chalcogenide open frameworks constructed from unusual defective supertetrahedral clusters and various kinds of linkers. Both the structures exhibit impressive architecture and high extra-framework volume ratios. [ABSTRACT FROM AUTHOR]

Herein, we report a simple, yet highly effective approach for constructing a new type of sub-nanoscale ZnS/ZnO heterojunction (∼2–4 nm) with highly rich interfaces by photoetching hybrid Zn–S–O molecular clusters. The obtained ZnS/ZnO heterojunctions with ZnS spheres decorated with ultrasmall amorphous ZnO dots exhibit superior photocatalytic performance (∼94.0 μmol g−1 h−1), compared to nanoscale homologous samples obtained via conventional heat treatment (∼17.0–21.4 μmol g−1 h−1). Such a light-triggered molecular-cluster-to-heterojunction strategy provides a synthetic approach to building other sub-nanoscale hetero-structured materials for further promoting the catalytic-related applications. [ABSTRACT FROM AUTHOR]

Reported here are three new metal chalcogenide open frameworks built from supertetrahedral [In35S52O8] (denoted as T5-InOS or o-T5) and [In10S20] (denoted as T3-InS) nanoclusters of different sizes and compositions via co-assembly and/or hybrid assembly modes. Such a set of cluster-based superlattices with dia topological structures clearly exhibit quantum size effects and electronic coupling interaction of adjacent nanoclusters, which can effectively explain that the band gap of the T3–(o-T5) hybrid-assembled material lies in the middle of T3–T3 and (o-T5)–(o-T5) co-assembled materials. [ABSTRACT FROM AUTHOR]

Compared to typical Mn2+-doped II–VI nanocrystals with orange emission, Mn2+-doped II–III–VI metal-chalcogenide supertetrahedral nanoclusters with atomically precise structure have been proven to exhibit Mn2+-related red emission due to intrinsic intracluster torsion stress. How to explore and determine the effects of intercluster torsional strain on the Mn2+-related emission remains a challenge due to the lack of suitable structure models. Herein, two special nanocluster-based layered metal chalcogenides, composed of the same type of nanoclusters, but with different intercluster connections and a different-degree torsional structure, were created to explore the Mn2+-related photoluminescence emission. These current results clearly demonstrate that apart from the intracluster crystal lattice torsional strain, the intercluster torsion stress still serves as one of the major factors in effectively tuning Mn2+-related emission, and a larger intercluster torsion stress could lead to the redshift of the Mn2+-related emission. [ABSTRACT FROM AUTHOR]

We demonstrated here a novel semiconducting metal-chalcogenide–organic framework (MCOF-89) with an optical bandgap through the unlikely assembly between a metal chalcogenide unit and carboxylic acid. The elusive metal-chalcogenide unit [Mn4(μ4-S)] with square-planar tetra-coordinated sulfur (sptS) is for the first time observed in MOFs. [ABSTRACT FROM AUTHOR]

Herein we report a new 3D neutral chalcogenide framework constructed by using a supertetrahedral T3 cluster ([Mn2Ga4Sn4S20]) as the building unit and a metal complex ([Mn(dach)2], dach = 1,2-diaminocyclohexane) as the linker. Significantly, the obtained material exhibits high-efficiency electrocatalytic oxygen reduction activity with quasi-four-electron transfer and a small Tafel slope, much better than that of commercial Pt/C (10 wt%). [ABSTRACT FROM AUTHOR]

Reported here is a unique non-interpenetrated open-framework metal chalcogenide built on a supertetrahedral [Fe4In16S35]14− cluster. The non-interpenetrated feature accompanied with the relatively large-sized cluster leads to a high extra-framework volume. [ABSTRACT FROM AUTHOR]

We demonstrated here the first case of a vertex–edge connection mode in a three-dimensional open-framework chalcogenide built from the largest known T5 cluster. Such connection relies on a tri-coordinated edge sulfur atom, which serves as the linkage to bridge two adjacent T5 clusters. The architecture of the resulting structure can be classified as the infinite order of super-supertetrahedral T5 clusters (T5, ∞). [ABSTRACT FROM AUTHOR]

Multicomponent MOFs have offered a wide range of opportunities to harness new properties. However, the synthesis of multicomponent MOFs remains challenging. This work demonstrates the synthesis of a family of multicomponent MOFs by topological transformation from well-established multicomponent partitioned acs (pacs) structures. Such transformation is based on the new understanding on the self-assembly process of pacs MOFs. A key to this understanding is that pacs structures, topologically regarded as the introduction of a pore-partitioning ligand into MOF-235/MIL-88 type framework, are likely to be formed in a layer-pillar-layer fashion in practical reactions. As the π-π interaction between layers and other chemical interactions during the self-assembly process are recognized, the structural transformation can be modulated from 3D pacs structures to 2D interrupted pacs structures (denoted i-pacs). It is especially noteworthy that such dimensional reduction is first observed in metal-organic frameworks and the i-pacs MOFs contain four structural modules and up to five components, which have the highest complexity among 2D MOFs. Interestingly, the i-pacs MOFs have significantly enhanced performance for CO 2 /N 2 separation in comparison with pacs MOFs., (© 2024 Wiley‐VCH GmbH.)

Reported here are two unprecedented copper-rich open-framework chalcogenides constructed from unusual [Cu 5 (Sn x M 1- x )Se 10 ] clusters and [(Sn x M 1- x ) 2 Se 6 ] dimeric linkers (M = In and Ga). The photoresponsive properties in the IR range and the photocatalytic activity for degradation of methylene blue dye of these two isostructural semiconductors were proved to be effectively adjusted by trivalent metal ions in a cluster.

Strong Mn-Mn coupling interactions (dipole-dipole and spin-exchange), predominantly determined by statistically and apparently short Mn···Mn distances in traditional heavily Mn 2+ -doped semiconductors, can promote energy transfer within randomly positioned and close-knit Mn 2+ pairs. However, the intrinsic mechanism on controlling Mn 2+ emission efficiency is still elusive due to the lack of precise structure information on local tetrahedrally coordinated Mn 2+ ions. Herein, a group of Mn 2+ -containing metal-chalcogenide open frameworks ( MCOFs ), built from [Mn 4 In 16 S 35 ] nanoclusters (denoted T4-MnInS) with a precise [Mn 4 S] configuration and length-variable linkers, were prepared and selected as unique models to address the above-mentioned issues. MCOF-5 and MCOF-6 that contained a symmetrical [Mn 4 S] core with a D 2 d point group and relatively long Mn···Mn distance (∼3.9645 Å) exhibited obvious red emission, while no room-temperature PL emission was observed in MCOF-7 that contained an asymmetric [Mn 4 S] configuration with a C 1 point group and relatively short Mn···Mn distance (∼3.9204 Å). The differences of Mn-Mn dipole-dipole and spin-exchange interactions were verified through transient photoluminescent spectroscopy, electron spin resonance (ESR), and magnetic measurements. Compared to MCOF-5 and MCOF-6 showing a narrower/stronger ESR signal and longer decay lifetime of microseconds, MCOF-7 displayed a much broader/weaker ESR signal and shorter decay lifetime of nanoseconds. The results demonstrated the dominant role of distance-directed Mn-Mn dipole-dipole interactions over symmetry-directed spin-exchange interactions in modulating PL quenching behavior of Mn 2+ emission. More importantly, the reported work offers a new pathway to elucidate Mn 2+ -site-dependent photoluminescence regulation mechanism from the perspective of atomically precise nanoclusters.

The direct electroreduction of CO2 to ratio-tunable syngas (CO + H2) is an appealing solution to provide important feedstocks for many industrial processes. However, low-cost, Earth-abundant yet efficient and stable electrocatalysts for composition-adjustable syngas have still not been realized for practical applications. Herein, new hierarchical 0D/2D heterostructures of SnO2 nanoparticles (NPs) confined on CuS nanosheets (NSs) were designed to enable CO2 electroreduction to a wide-range syngas (CO/H2: 0.11-3.86) with high faradaic efficiency (>85%), remarkable turnover frequency (96.12 h-1) and excellent durability (over 24 h). Detailed experimental characterization studies together with theoretical calculations manifest that the ascendant catalytic performance is not only attributed to the heterostructure of ultrasmall SnO2 NPs homogeneously confined on ultrathin CuS NSs, which endows the maximum exposure of active sites and faster charge transfer, but is also accounted by the strong interaction between well-defined SnO2 and CuS interfaces, which modulated reaction free-energies of reaction intermediates and hence improved the activity of CO2 electroreduction to highly ratio-tunable syngas. This work provides a better understanding and a new strategy for intermediate regulation by interface engineering of hereostructures for CO2 reduction and beyond.

Reported here is a unique crystalline semiconductor open-framework material built from the large-sized supertetrahedral T4 and T5 clusters with the Mn-In-S compositions. The hybrid assembly between T4 and T5 clusters by sharing terminal μ 2 -S 2- is for the first time observed among the cluster-based chalcogenide open frameworks. Such three-dimensional structure displays non-interpenetrated diamond-type topology with extra-large nonframework volume of 82%. Moreover, ion exchange, CO 2 adsorption, as well as photoluminescence properties of the title compound are also investigated.

The highly efficient and cheap non-Pt-based electrocatalysts such as transition-based catalysts prepared via facile methods for oxygen reduction reaction (ORR) are desirable for large-scale practical industry applications in energy conversion and storage systems. Herein, we report a straightforward top-down synthesis of monodisperse ultrasmall manganese-doped multimetallic (ZnGe) oxysulfide nanoparticles (NPs) as an efficient ORR electrocatalyst by simple ultrasonic treatment of the Mn-doped Zn-Ge-S chalcogenidometalate crystal precursors in H 2 O/EtOH for only 1 h at room temperature. Thus obtained ultrasmall monodisperse Mn-doped oxysulfide NPs with ultralow Mn loading level (3.92 wt %) not only exhibit comparable onset and half-wave potential (0.92 and 0.86 V vs reversible hydrogen electrode, respectively) to the commercial 20 wt % Pt/C but also exceptionally high metal mass activity (189 mA/mg at 0.8 V) and good methanol tolerance. A combination of transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, and electrochemical analysis demonstrated that the homogenous distribution of a large amount of Mn(III) on the surface of NPs mainly accounts for the high ORR activity. We believe that this simple synthesis of Mn-doped multimetallic (ZnGe) oxysulfide NPs derived from chalcogenidometalates will open a new route to explore the utilization of discrete-cluster-based chalcogenidometalates as novel non-Pt electrocatalysts for energy applications and provide a facile way to realize the effective reduction of the amount of catalyst while keeping desired catalytic performances.

Unexpected nonlinear variation in the composition and optical band gap was observed in an alloyed open-framework metal chalcogenide composed of supertetrahedral clusters. A tentative hypothesis was proposed to explain how the title compound [In 28 Se 54 (H 2 O) 4 ]·24H + -PR· nH 2 O (PR = piperidine) exhibits a limitation in the S-alloying level and a large variation in the optical band gap.

Reported here is a new metal chalcogenide semiconductor with the double-interpenetrated zeolitic nabesite framework, which is constructed by the rare extended spiro-5 units with supertetrahedral clusters serving as building units. Different from the TO 4 -based simple spiro-5 unit frequently observed in oxide-based zeolites, the extended spiro-5 unit composed of five supertetrahedral T3-InSnS clusters is for the first time observed in the family of open-framework metal chalcogenides. Such secondary building units finally assemble into a rare NAB topological framework with large external space. In addition, the title semiconductor material also displays good properties in photocurrent response and electrocatalytic oxygen reduction reaction.

Developing the structural diversity of microporous zeolitic frameworks with integrated semiconducting properties is promising but remains a challenge. Reported here are two unique crystalline semiconductor zeolite analogues constructed from two kinds of indium selenide clusters with augmented ctn and zeolite-type sod networks. The intrinsic semiconducting nature in these In-Se domains gives rise to pore-size-dependent and visible-light-driven photocatalytic activity for organic dye degradation.