Visibility of hexagonal boron nitride on transparent substrates.

The high transmittance and low reflectance of monolayer hexagonal boron nitride (hBN) lead to its invisibility under white-light, causing serious troubles in the search, transfer, and fabrication of 2D material devices. In this work, we demonstrate enhancing the contrast of hBN on a transparent substrate by simulation and experimental observation, where the highest contrast is obtained by using a polymer-based interfacial layer on a polydimethylsiloxane (PDMS) substrate. The simulation result reveals that the contrast under short wavelength light is higher than that under long wavelength.

Fabrication of Robust Hydrogen Evolution Reaction Electrocatalyst Using AgSe by Vacuum Evaporation.

Much research has been done on reliable and low-cost electrocatalysts for hydrogen generation by water splitting. In this study, we synthesized thin films of silver selenide (AgSe) using a simple thermal evaporation route and demonstrated their electrocatalytic hydrogen evolution reaction (HER) activity. The AgSe catalysts show improved electrochemical surface area and good HER electrocatalytic behavior (367 mV overpotential @ 10 mA·cm, exchange current density: ~1.

Visualizing Degradation of Black Phosphorus Using Liquid Crystals.

Black Phosphorus (BP) is an excellent material from the post graphene era due to its layer dependent band gap, high mobility and high I/I. However, its poor stability in ambient poses a great challenge for its practical and long-term usage. The optical visualization of the oxidized BP is the key and the foremost step for its successful passivation from the ambience.

Correction: A vertical WSe-MoSe p-n heterostructure with tunable gate rectification.

[This corrects the article DOI: 10.1039/C8RA03398F.].

A vertical WSe-MoSe p-n heterostructure with tunable gate rectification.

Here, we report the synthesis of a vertical MoSe/WSe p-n heterostructure using a sputtering-CVD method. Unlike the conventional CVD method, this method produced a continuous MoSe/WSe p-n heterostructure. WSe and MoSe back-gated field effect transistors (FETs) exhibited good gate modulation behavior, and high hole and electron mobilities of ∼2.

Temperature-Dependent and Gate-Tunable Rectification in a Black Phosphorus/WS van der Waals Heterojunction Diode.

Heterostructures comprising two-dimensional (2D) semiconductors fabricated by individual stacking exhibit interesting characteristics owing to their 2D nature and atomically sharp interface. As an emerging 2D material, black phosphorus (BP) nanosheets have drawn much attention because of their small band gap semiconductor characteristics along with high mobility. Stacking structures composed of p-type BP and n-type transition metal dichalcogenides can produce an atomically sharp interface with van der Waals interaction which leads to p-n diode functionality.