We developed a multi-level lithography process to fabricate graphene p-n-p junctions with contactless, suspended top gates. This fabrication procedure minimizes damage or doping to the single atomic layer, which is only exposed to conventional resists and developers. The process does not require special equipment for depositing gate dielectrics or releasing sacrificial layers, and is compatible with annealing procedures that improve device mobility.Using this technique, we fabricate graphene devices with suspended local top gates, where the creation of high quality graphene p-n-p junctions is confirmed by transport data at zero and high magnetic fields.

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Inspired by the synthesis of Janus MoSSe and its beneficial properties, we here report for the first time the adsorption and diffusion of Li-ion on the single-layer MoSSe (SLM) and the double-layer MoSSe (DLM) using first-principle computations. The results show that much more Li-ions can be stored by the SLM and DLM due to their intrinsic dipole moment and the charge redistribution. With a suitable open circuit voltage range vs Li+/Li, the ideal theoretical capacities for the SLM and DLM are 776.5 and 452.9 mAh/g, respectively. Furthermore, the calculated density of states of the lithiated SLM and DLM indicates that they have good electrical conduction, and the smaller Li-ion/Li-vacancy migration barrier ensures fast Li-ion diffusion. Our results suggest that the SLM and DLM can be utilized as a potential anode material for high-performance Li-ion batteries.

Linear and hyperbranched poly(azomethine)s (PAMs)-based on triphenylamine moieties are synthesized and used as the functioning layers in the Ta/PAM/Pt resistive switching memory devices. Comparably, the hyperbranched PAM with isotropic architecture and semi-crystalline nature shows enhanced memory behaviors with more uniform distribution of the HRS and LRS resistances.