Bottom-up design of functional device components based on nanometer-sized building blocks relies on accurate control of their self-assembly behavior. Atom-precise metal nanoclusters are well-characterizable building blocks for designing tunable nanomaterials, but it has been challenging to achieve directed assembly to macroscopic functional cluster-based materials with highly anisotropic properties. Here, we discover a solvent-mediated assembly of 34atom intermetallic gold-silver clusters protected by 20 1-ethynyladamantanes into 1D polymers with Ag-Au-Ag bonds between neighboring clusters as shown directly by the atomic structure from single-crystal X-ray diffraction analysis. Density functional theory calculations predict that the single crystals of cluster polymers have a band gap of about 1.3 eV. Fieldeffect transistors fabricated with single crystals of cluster polymers feature highly anisotropic p-type semiconductor properties with ≈1800-fold conductivity in the direction of the polymer as compared to cross directions, hole mobility of ≈0.02 cm 2 V −1 s −1 , and an ON/OFF ratio up to ≈4000. This performance holds promise for further design of functional cluster-based materials with highly anisotropic semiconducting properties.

Crown ether effectively stabilizes the cubic phase of CsPbI3 to inhibit the moisture invasion and phase transformation of CsPbI3 films, producing large-area devices and improving device performance.

Perovskite films prepared with CH3NH2 molecules under ambient conditions have led to rapid fabrication of perovskite solar cells (PSCs), but there remains a lack of mechanistic studies and inconsistencies with operability in their production. Here the crystal structure of CH3NH2–CH3NH3PbI3 was analyzed to involve hydrogen bonds (CH3NH2···CH3NH3 +) and has guided the facile, reproducible preparation of high-quality perovskite films under ambient conditions. Hydrogen bonds within CH3NH2···CH3NH3 + dimers were found in the CH3NH2–CH3NH3PbI3 intermediates, accompanied by 1D-PbI3 – chains (δ-phase). The weakly hydrogen-bonded CH3NH2 molecules were easily released from the CH3NH2–CH3NH3PbI3 intermediates, contributing to rapid, spontaneous phase transition from 1D-PbI3 – (δ-phase) to 3D-PbI3 – (α-phase). Further introduction of CH3NH3Cl into the CH3NH2–CH3NH3PbI3 intermediates led to interruption of 1D-PbI3 – transition into 0D-Pb2I9‑x Cl x 5–(0 < x < 6), adjusting the phase transition route toward 3D-PbI3 –. On the basis of the above understanding, CH3NH2 solution in ethanol and CH3NH3Cl were used for precursors and a best efficiency of 20.3% in PSCs was achieved. Large-scale modules (12 cm2 aperture area) fabricated by a dip-coating technology exhibited an efficiency up to 16.0% and outstanding stability over 10 000 s under continuous output. The developed preparation method of perovskite precursors and insightful research into the methylamine-dimer-induced phase transition mechanism have enabled the production of high-quality perovskite films with robust operability, showing great potential for large-scale commercialization.

Atomically dispersed catalysts have demonstrated superior catalytic performance in many chemical transformations. However, limited success has been achieved in applying oxide-supported atomically dispersed catalysts to semihydrogenation of alkynes under mild conditions. By utilizing various metal oxides (e.g., Cu2O, Al2O3, ZnO, and TiO2) as supports for atomically dispersed Pd catalysts, we demonstrate herein the critical role of the oxidation state and coordinate environment of Pd centers in their catalytic performance, thus leading to the discovery of an “oxide-support effect” on atomically dispersed metal catalysts. Pd atomically dispersed on Cu2O exhibits far better catalytic activity in the hydrogenation of alkynes, with an extremely high selectivity toward alkenes, compared to catalysts on other oxides. Pd species galvanically displace surface Cu(I) sites on Cu2O to create two-coordinated Pd(I), which is a critical step for the activation and heterolytic splitting of H2 into Pd-H− and O-H+ species for the selective hydrogenation of alkynes. Moreover, the adsorption of alkenes on H2-preadsorbed Pd(I) is relatively weak, preventing deeper hydrogenation and increased selectivity during semihydrogenation. We demonstrate that the local coordinate environment of active metal centers plays a crucial role in determining the catalytic performance of an oxide-supported atomically dispersed catalyst.

A novel gold-catalyzed intermolecular ynamide amination-initiated aza-Nazarov cyclization has been developed, allowing the facile and efficient synthesis of various 2-aminopyrroles in moderate to good yields. Furthermore, a mechanistic rationale for this tandem sequence, especially for the observed high regioselectivity, is also well supported by DFT (density functional theory) computations. The high flexibility, broad substrate scope, and mild nature of this reaction render it a viable alternative for the construction of 2-aminopyrroles.

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A Lewis acid-catalyzed alkyne oxidation strategy has been developed to produce diverse α-functionalized amides from readily and generally available ynamides. An efficient zinc­(II)-catalyzed oxidative azidation and thiocyanation has been achieved, providing facile access to synthetically useful α-azido amides and α-thiocyanate amides, respectively. This chemistry can also be extended to oxidative halogenations by employing the 2-halopyridine N-oxide as both the oxidant and the halogen source, and its mechanistic rationale is also supported by density functional theory calculations. Moreover, NaBARF has been demonstrated to catalyze such an alkyne oxidation effectively, thus further excluding the metal carbene pathway in this cascade reaction.

A novel zinc-catalyzed intermolecular oxidation of N-sulfonyl ynamides has been developed. A variety of functionalized α,β-unsaturated N-sulfonyl imides are readily accessed by utilizing this approach, thus providing a viable alternative to synthetically useful α,β-unsaturated imides. Importantly, the reaction is proposed to proceed by a vinyligous E2-type elimination pathway, but not metal carbene pathway.