Noble‐metal chalcogenides, dichalcogenides, and phosphochalcogenides are an emerging class of two‐dimensional materials. Quantum confinement (number of layers) and defect engineering enables their properties to be tuned over a broad range, including metal‐to‐semiconductor transitions, magnetic ordering, and topological surface states. They possess various polytypes, often of similar formation energy, which can be accessed by selective synthesis approaches. They excel in mechanical, optical, and chemical sensing applications, and feature long‐term air and moisture stability. In this Minireview, we summarize the recent progress in the field of noble‐metal chalcogenides and phosphochalcogenides and highlight the structural complexity and its impact on applications.

van der Waals heterostructures are currently the focus of intense investigation; this is essentially due to the unprecedented flexibility offered by the total relaxation of lattice matching requirements and their new and exotic properties compared to the individual layers. Here, we investigate the hybrid transition-metal dichalcogenide/2D perovskite heterostructure WS 2 / (PEA) 2 PbI 4 (where PEA stands for phenylethylammonium). We present the first density functional theory (DFT) calculations of a heterostructure ensemble, which reveal a novel band alignment, where direct electron transfer is blocked by the organic spacer of the 2D perovskite. In contrast, the valence band forms a cascade from WS 2 through the PEA to the PbI 4 layer allowing hole transfer. These predictions are supported by optical spectroscopy studies, which provide compelling evidence for both charge transfer and nonradiative transfer of the excitation (energy transfer) between the layers. Our results show that TMD/2D perovskite (where TMD stands for transition-metal dichalcogenides) heterostructures provide a flexible and convenient way to engineer the band alignment.

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Investigation of 2D perovskite/MoSe2 heterostructures shows that the charge transfer leads to the formation of inter-layer excitons.

A promising strategy for new electrically conductive coordination polymers is the combination of d 10 metal ions, which tolerate short metal•••metal distances, with dithiolene linkers, known for their "non-innocent" redox behavior. This study explores the coordination chemistry of 2,3-pyrazinedithiol (H 2 pdt) toward Cu + and Ag + ions, highlighting similarities and differences. The synthetic approach, starting with the fully protonated ligand, allowed the isolation of a homoleptic bis(dithiolene) complex with formal Cu I atoms, [Cu(H 2 pdt) 2 ]Cl (1). This complex was further transformed to a 1D coordination polymer with short metal•••metal distances, 1D [Cu(Hpdt)] (2 Cu ). The larger Ag + ion directly built up a very similar coordination polymer, 1D [Ag(Hpdt)] (2 Ag ), without any appearance of an intermediate metal complex. The coordination polymer 1D [Cu(H 2 pdt)I] (4), like complex 1, bears fully protonated H 2 pdt ligands in their dithione form. Upon heating, both compounds underwent auto-oxidation coupled with a dehydrogenation of the ligand to form the open-shell neutral copper(II) complex [Cu(Hpdt) 2 ] (3) and the coordination polymer 1D [Cu 2 I 2 (H 2 pdt)(Hpdt)] (5), respectively. For all presented compounds, crystal structures are discussed in-depth. Furthermore, properties of 1, 3, and those of the three 1D coordination polymers, 2 Ag , 2 Cu , and 4, were investigated by UV−vis−NIR spectroscopy, cyclic voltammetry, and variabletemperature magnetic susceptibility, and direct current (dc)-conductivity measurements. The experimental results are compared and discussed with the aid of DFT simulations.