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Monolayer MoS2 has attracted significant attention owing to its excellent performance as an n‐type semiconductor from the transition metal dichalcogenide (TMDC) family. It is however strongly desired to develop controllable synthesis methods for 2D p‐type MoS2, which is crucial for complementary logic applications but remains difficult. In this work, high‐quality NbS2–MoS2 lateral heterostructures are synthesized by one‐step metal–organic chemical vapor deposition (MOCVD) together with monolayer MoS2 substitutionally doped by Nb, resulting in a p‐type doped behavior. The heterojunction shows a p‐type transfer characteristic with a high on/off current ratio of ≈104, exceeding previously reported values. The band structure through the NbS2–MoS2 heterojunction is investigated by density functional theory (DFT) and quantum transport simulations. This work provides a scalable approach to synthesize substitutionally doped TMDC materials and provides an insight into the interface between 2D metals and semiconductors in lateral heterostructures, which is imperative for the development of next‐generation nanoelectronics and highly integrated devices.

A first-principles theoretical study of a monolayer-thick lateral heterostructure (LH) joining two different transition metal dichalcogenides, NbS 2 and WSe 2 , is reported. The NbS 2 //WSe 2 LH can be considered a prototypical example of a metal (NbS 2)/semiconductor (WSe 2) 2D hybrid heterojunction. First, realistic atomistic models of the NbS 2 //WSe 2 LH are generated and validated, its band structure is derived, and it is subjected to a fragment decomposition and electrostatic potential analysis to extract a simple but quantitative model of this interfacial system. Stoichiometric fluctuations models are also investigated and found not to alter the qualitative picture. Then, electron transport simulations are conducted and they are analyzed via band alignment analysis. It is concluded that the NbS 2 //WSe 2 LH appears as a robust seamless in-plane 2D modular junction for potential use in optoelectronic devices going beyond the present miniaturization technology.

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Thermoelectric properties of a polyaniline molecular junction with face centered cubic electrodes are investigated using the Green function formalism in a linear response regime in the presence of the doping process. Doping causes the increase of thermopower and the figure of merit (ZT) and the decrease of electrical conductance as found experimentally in the work of Li et al., (Synthetic. Metals, 2010, 160, 1153-1158). We also find that the ZT increases with the molecular length in short polyanilines. [Golsanamlou et al., Phys. Chem. Chem. Phys., 2000, 35, 3523].

Thermal and electron transport through organic molecules attached to three-dimensional gold electrodes in two different configurations, namely para and meta with thiol-terminated junctions is studied theoretically in the linear response regime using Green's function formalism. We used thiol-terminated (-SH bond) benzene units and found a positive thermopower because the highest occupied molecular orbital (HOMO) is near the Fermi energy level. We investigated the influence of molecular length and molecular junction geometry on the thermoelectric properties. Our results show that the thermoelectric properties are highly sensitive to the coupling geometry and the molecular length. In addition, we observed that the interference effects and increasing molecular length can increase the thermoelectric efficiency of device in a specific configuration.