Because of their unique atomic structure, 2D materials are able to create an up-to-date paradigm in fundamental science and technology on the way to engineering the band structure and electronic properties of materials on the nanoscale. One of the simplest methods along this path is the superposition of several 2D nanomaterials while simultaneously specifying the twist angle between adjacent layers (θ), which leads to the emergence of Moirésuperlattices. The key challenge in 2D nanoelectronics is to obtain a nanomaterial with numerous Moirésuperlattices in addition to a high carrier mobility in a stable and easy-to-fabricate material. Here, we demonstrate the possibility of synthesizing twisted multilayer graphene (tMLG) with a number of monolayers N L = 40−250 and predefined narrow ranges of θ = 3−8°, θ = 11−15°, and θ = 26−30°. A 2D nature of the electron transport is observed in the tMLG, and its carrier mobilities are close to those of twisted bilayer graphene (tBLG) (with θ = 30°) between h-BN layers. We demonstrate an undoubtful presence of numerous Moirésuperlattices simultaneously throughout the entire tMLG thickness, while the periods of these superlattices are rather close to each other. This offers a challenge of producing a next generation of devices for nanoelectronics, twistronics, and neuromorphic computing for large data applications.

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2D conjugated polyphthalocyanines can be obtained as two distinctly different types of material with specific molecular structures and different morphological properties. It was believed that the temperature is the key factor affecting the chemical reaction, but we show that even at the optimal temperature (420 °C), the reaction on vapor/solid interface and liquid/solid interface yields different products: while the former is well-polymerized and ordered, the latter is amorphous and cross-linked with the typical conjugation scale of single phthalocyanine (PC) ring. Infrared spectroscopy is most sensitive tool for identifying the molecular structure, providing the information on polymerization degree, structural uniformity and content of terminal groups. We show that, unlike the ordered polyphthalocyanines, the cross-linked product can be reproducibly obtained as continuous conductive material.

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