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Heterostructures of two‐dimensional materials realise novel and enhanced physical phenomena, making them attractive research targets. Compared to inorganic materials, coordination nanosheets have virtually infinite combinations, leading to tunability of physical properties and are promising candidates for heterostructure fabrication. Although stacking of coordination materials into vertical heterostructures is widely reported, reports of lateral coordination material heterostructures are few. Here we show the successful fabrication of a seamless lateral heterojunction showing diode behaviour, by sequential and spatially limited immersion of a new metalladithiolene coordination nanosheet, Zn3BHT, into aqueous Cu(II) and Fe(II) solutions. Upon immersion, the Zn centres in insulating Zn3BHT are replaced by Cu or Fe ions, resulting in conductivity. The transmetallation is spatially confined, occurring only within the immersed area. We anticipate that our results will be a starting point towards exploring transmetallation of various two‐dimensional materials to produce lateral heterojunctions, by providing a new and facile synthetic route. [ABSTRACT FROM AUTHOR]

Recent studies on molecular 2D materials with high tunability of structure and function have focused mostly on the discovery of new precursors. Here, we demonstrate a facile one‐pot synthesis of laminated 2D coordination polymer films comprising bis(terpyridine)iron and cobalt at a water/dichloromethane interface. Cross‐sectional elemental mapping unveiled the stratum‐like structure of the film and revealed that the second layer grows to the dichloromethane side below the first layer. Cyclic voltammetry clarified that the bottom layer mediates charge transfer between the top layer and the substrate in a narrow potential region of mixed‐valence states. Furthermore, the bilayer film sandwiched by electrodes in a dry condition shows stable rectification character, and the barrier voltage corresponds to the redox potential difference between the two layers. This study introduces a new strategy for polymer design to explore the materials science of molecular 2D materials. [ABSTRACT FROM AUTHOR]

Organometallic two‐dimensional (2D) nanosheets with tailorable components have recently fascinated the optoelectronic communities due to their solution‐processable nature. However, the poor stability of organic molecules may hinder their practical application in photovoltaic devices. Instead of conventional organometallic 2D nanosheets with low weatherability, an air‐stable π‐conjugated 2D bis(dithiolene)iron(II) (FeBHT) coordination nanosheet (CONASH) is synthesized via bottom‐up liquid/liquid interfacial polymerization using benzenehexathiol (BHT) and iron(II) ammonium sulfate [Fe(NH4)2(SO4)2] as precursors. The uncoordinated thiol groups in FeBHT are easily oxidized, but the Fe(NH4)2(SO4)2 dissociation rate is slow, which facilitates the protection of sulfur groups by iron(II) ions. The density functional theory calculates that the resultant FeBHT network gains the oxygen‐repelling function for oxidation suppression. In air, the FeBHT CONASH exhibits self‐powered photoresponses with short response times (<40 ms) and a spectral responsivity of 6.57 mA W−1, a specific detectivity of 3.13 × 1011 Jones and an external quantum efficiency of 2.23% under 365 nm illumination. Interestingly, the FeBHT self‐powered photodetector reveals extremely high long‐term air stability, maintaining over 94% of its initial photocurrent after aging for 60 days without encapsulation. These results open the prospect of using organometallic 2D materials in commercialized optoelectronic fields. [ABSTRACT FROM AUTHOR]

In an article published in Angewandte Chemie International Edition, Hiroshi Nishihara et al. present a new method for creating lateral heterojunctions in two-dimensional materials. These heterojunctions have rectifying properties and are formed by immersing a coordination nanosheet made from zinc ions and benzenehexathiol into iron and copper salt solutions. This research has implications for utilizing the attractive properties of two-dimensional materials more effectively. The authors of the article include Choon Meng Tan, Naoya Fukui, Kenji Takada, Hiroaki Maeda, Ekaterina Selezneva, Cédric Bourgès, Hiroyasu Masunaga, Sono Sasaki, Kazuhito Tsukagoshi, Takao Mori, Henning Sirringhaus, and Hiroshi Nishihara. [Extracted from the article]

In an article published in Angewandte Chemie, Hiroshi Nishihara et al. present a new method for creating lateral heterojunctions in two-dimensional materials. These heterojunctions have rectifying properties and can be fabricated by immersing a coordination nanosheet made from zinc ions and benzenehexathiol into iron and copper salt solutions. This research has implications for utilizing the attractive properties of two-dimensional materials more effectively. The authors of the article include Choon Meng Tan, Naoya Fukui, Kenji Takada, Hiroaki Maeda, Ekaterina Selezneva, Cédric Bourgès, Hiroyasu Masunaga, Sono Sasaki, Kazuhito Tsukagoshi, Takao Mori, Henning Sirringhaus, and Hiroshi Nishihara. [Extracted from the article]

The heterolaminated films show unique redox behavior based on electron transfer mediation, and a stable rectification character owing to the difference in electron transfer kinetics between the two layers. Front Cover: Chemically Laminated 2D Bis(terpyridine)metal Polymer Films: Formation Mechanism at the Liquid-Liquid Interface and Redox Rectification (Chem. Eur. J. 44/2022) Keywords: 2D materials; electron transfer; heterolayers; metal complexes; polymers EN 2D materials electron transfer heterolayers metal complexes polymers 1 1 1 08/08/22 20220804 NES 220804 B Heterolaminated bis(terpyridine)metal films b have been prepared by sequential coordination at the H SB 2 sb O/CH SB 2 sb Cl SB 2 sb interface. [Extracted from the article]

ABSTRACT To develop a microscale processing technique for aromatic polyimides (APIs) in supercritical carbon dioxide (scCO2), the relationships between the polymerization condition, the phase behavior during polymerization and the molecular weight of polyamic acid (PAA)-an intermediate in the production of polyimides-were investigated in scCO2 at 50°C. 4,4′-Diaminodiphenyl ether (ODA) and pyromellitic dianhydride (PMDA) were used as monomers of aromatic diamine and tetracarboxylic dianhydride, respectively, and 19 mol % of N,N-Dimethylformamide (DMF) was added to scCO2 as a cosolvent. The cloudy phase appeared immediately when ODA and PMDA were mixed under any experimental conditions. However, the appearances of the phase behaviors during polymerization differed depending on the polymerization pressure and the initial monomer concentration. The number average molecular weight of PAA increased as the monomer concentration was increased in scCO2, as was the case with polymerization in pure DMF at atmospheric pressure, despite differences in the phase behavior. On the other hand, the weight average molecular weight of PAA depended on the phase behaviors during polymerization along with the monomer concentration. Moreover, API obtained from the PAA synthesized in scCO2 was analyzed using a Fourier transform infrared spectrophotometer and thermogravimetric analyzer, and the results were compared with those of APIs obtained by the solution polymerization. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39878. [ABSTRACT FROM AUTHOR]

Self-Powered UV Photodetectors: Two-Dimensional Bis(dithiolene)iron(II) Self-Powered UV Photodetectors with Ultrahigh Air Stability (Adv. Sci. 14/2021) Two-dimensional organic-inorganic materials have been unable to break the bottleneck of photocurrent generation without external bias due to their poor electrical properties. Moreover, the selfpowered photodetectors maintained 94% of their initial photocurrent after 60 days of aging in air without encapsulation. [Extracted from the article]