m all existing carbon materials. Macroscale tensile tests yields maximum values of 62 GPa for the Young's modulus and 0.70 GPa for the fracture strength, significantly higher than has been reported for any other macroscale carbon films; microscale tensile tests yield maximum values of 290 GPa for the Young's modulus and 5.8 GPa for the fracture strength. The measured in-plane thermal conductivity is exceptionally high, 2292 ± 159 W m^-1 K^-1 while in-plane electrical conductivity is 2.2 × 10⁵ S m^-1 . The high performance of these films is attributed to the combination of the high in-plane crystalline order and unique stacking configuration through the thickness.22:T497,Black phosphorus (BP) has recently emerged as an alternative 2D semiconductor\nowing to its fascinating electronic properties such as tunable bandgap and high\ncharge carrier mobility. The structural investigation of few-layer BP, such as\nidentification of layer thickness and atomic-scale edge structure, is of great\nimportance to fully understand its electronic and optical properties. Here we\nreport atomic-scale analysis of few-layered BP performed by aberration\ncorrected transmission electron microscopy (TEM). We establish the\nlayer-number-dependent atomic resolution imaging of few-layer BP via TEM\nimaging and image simulations. The structural modification induced by the\nelectron beam leads to revelation of crystalline edge and formation of BP\nnanoribbons. Atomic resolution imaging of BP clearly shows the reconstructed\nzigzag (ZZ) edge structures, which is also corroborated by van der Waals first\nprinciples calculations on the edge stability. Our study on the precise\nidentification of BP thickness and atomic-resolution imaging of edge structures\nwill lay the groundwork for investigation of few-layer BP, especially BP in\nnanostructured forms.\n23:T453,The van der Waals epitaxy of functional materials provides an interesting and efficient way to manipulate the electrical properties of various hybrid two-dimensional (2D) systems. Here we show the controlled epitaxial assembly of semiconducting one-dimensional (1D) atomic chains, AuCN, on graphene and investigate the electrical properties of 1D/2D van der Waals heterostructures. AuCN nanowire assembly is tuned by different growth conditions, although the epitaxial alignment between AuCN chains and graphene remains unchanged. The switching of the preferred nanowire growth axis indicates that diffusion kinetics affects the nanowire formation process. Semiconducting AuCN chains endow the 1D/2D hybrid system with a strong responsivity to photons with an energy above 2.7 eV, which is consistent with the bandgap of AuCN. A large UV response (responsivity ∼10⁴ A/W) was observed under illumination using 3.1 eV (400 nm) photons. Our study clearly demonstrates that 1D chain-structured semiconductors can play a crucial role as a component in multifunctional van der Waals heterostructures.24:T4a8,Group IV monochalcogenides have recently shown great potential for their thermoelectric, ferroelectric, and other intriguing properties. The electrical properties of group IV monochalcogenides exhibit a strong dependence on the chalcogen type. For example, GeTe exhibits high doping concentration, whereas S/Se-based chalcogenides are semiconductors with sizable bandgaps. Here, we investigate the electrical and thermoelectric properties of γ-GeSe, a recently identified polymorph of GeSe. γ-GeSe exhibits high electrical conductivity (∼10⁶ S/m) and a relatively low Seebeck coefficient (9.4 μV/K at room temperature) owing to its high p-doping level (5 × 10²¹ cm^-3), which is in stark contrast to other known GeSe polymorphs. Elemental analysis and first-principles calculations confirm that the abundant formation of Ge vacancies leads to the high p-doping concentration. The magnetoresistance measurements also reveal weak antilocalization because of spin-orbit coupling in the crystal. Our results demonstrate that γ-GeSe is a uniq

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