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 abovementioned issues. MCOF-5 and MCOF-6 that contained a symmetrical [Mn 4 S] core with a D 2d 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.

Few multi-metal-based systems were created to probe the regulation mechanism in electrocatalytic reactions. Herein, we select supertetrahedral metal sulfide nanoclusters (MSNCs) with preconfined and precisely positioned multi-metal ions as a structure model and have successfully developed MSNC-based electrocatalysts. Unprecedentedly, those new materials based on M–Ga–Sn–S NCs (M = Mn, Co, and Zn) show the synergistic effect of multi-metal ions on hydrogen evolution reaction (HER) via experiments and density functional theory (DFT) calculations. Among various multi-metal possibilities studied here, the most efficient one is that codoped with Mn, Co, and Zn, and it achieves a low overpotential of 176 mV at 10 mA cm–2 and a small Tafel slope of 43 mV dec–1. Such unique model system allows for systematic investigation of catalytic activities of low-coordinated sulfur ions in well-defined chemical environment and could have long-lasting and fundamental impacts on creating new types of chalcogenide-based electrocatalysts.

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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.

Hierarchical heterostructure of SnO2 confined on ultrathin CuS nanosheets for efficient electrocatalytic CO2 reduction.