Charge Transfer Modulation in Vanadium-Doped WS /Bi O Se Heterostructures.

The field of photovoltaics is revolutionized in recent years by the development of two-dimensional (2D) type-II heterostructures. These heterostructures are made up of two different materials with different electronic properties, which allows for the capture of a broader spectrum of solar energy than traditional photovoltaic devices. In this study, the potential of vanadium (V)-doped WS is investigated, hereafter labeled V-WS , in combination with air-stable Bi O Se for use in high-performance photovoltaic devices.

Toward understanding the phase-selective growth mechanism of films and geometrically-shaped flakes of 2D MoTe.

Two-dimensional (2D) molybdenum ditelluride (MoTe) is an interesting material for fundamental study and applications, due to its ability to exist in different polymorphs of 2H, 1T, and 1T', their phase change behavior, and unique electronic properties. Although much progress has been made in the growth of high-quality flakes and films of 2H and 1T'-MoTe phases, phase-selective growth of all three phases remains a huge challenge, due to the lack of enough information on their growth mechanism. Herein, we present a novel approach to growing films and geometrical-shaped few-layer flakes of 2D 2H-, 1T-, and 1T'-MoTe by atmospheric-pressure chemical vapor deposition (APCVD) and present a thorough understanding of the phase-selective growth mechanism by employing the concept of thermodynamics and chemical kinetics involved in the growth processes.

Ultrathin BiOS nanosheet near-infrared photodetectors.

Recently, a zipper two-dimensional (2D) material BiOSe belonging to the layered bismuth oxychalcogenide (BiOX: X = S, Se, Te) family, has emerged as an alternate candidate to van der Waals 2D materials for high-performance electronic and optoelectronic applications. This hints towards exploring the other members of the BiOX family for their true potential and bismuth oxysulfide (BiOS) could be the next member for such applications. Here, we demonstrate for the first time, the scalable room-temperature chemical synthesis and near-infrared (NIR) photodetection of ultrathin BiOS nanosheets.

Elastic properties and breaking strengths of GaS, GaSe and GaTe nanosheets.

Gallium sulphide (GaS), gallium selenide (GaSe), and gallium telluride (GaTe), belonging to the group-III monochalcogenide family, have shown promising optoelectronic performance over graphene and monolayer molybdenum disulphide (MoS2). However, to date, the mechanical properties of these materials have not been investigated, which hinders their utilisation in flexible electronics and optomechanics. Here, we characterize the elastic properties and breaking strengths of suspended two-dimensional (2D) nanosheets of GaS, GaSe, and GaTe, using atomic force microscopy.

High-frequency electromechanical resonators based on thin GaTe.

Gallium telluride (GaTe) is a layered material, which exhibits a direct bandgap (∼1.65 eV) regardless of its thickness and therefore holds great potential for integration as a core element in stretchable optomechanical and optoelectronic devices. Here, we characterize and demonstrate the elastic properties and electromechanical resonators of suspended thin GaTe nanodrums.

Solution-Cast Photoconductive Photodetectors Based on CuInSe₂ Nanoparticles.

We, herein, report an eco-friendly low temperature route for the gram-scale synthesis of copper indium selenide nanoparticles. We have also shown the possibility of using CuInSe₂ nanoparticles in infrared photodetection by maneuvering the photoconductive property. We rationalize the long-lived trap states to be the cause for the observed photoconductive gain.

Water activated doping and transport in multilayered germanane crystals.

The synthesis of germanane (GeH) has opened the door for covalently functionalizable 2D materials in electronics. Herein, we demonstrate that GeH can be electronically doped by incorporating stoichiometric equivalents of phosphorus dopant atoms into the CaGe2 precursor. The electronic properties of these doped materials show significant atmospheric sensitivity, and we observe a reduction in resistance by up to three orders of magnitude when doped samples are measured in water-containing atmospheres.

Li intercalation into 1D TiS2(en) chains.

The intercalation of metal cations in 2D layered materials allows for the discovery of unique electronic, magnetic and correlated properties. We demonstrate that reversible Li intercalation is also achievable in the hybrid organic/inorganic dimensionally reduced 1D van der Waals solid TiS2(ethylenediamine). Upon intercalation, electrons are injected into the lattice as Ti(4+) is reduced to Ti(3+) leading to an order of magnitude decrease in electrical resistivity.

Infrared photodetectors based on reduced graphene oxide and graphene nanoribbons.

The use of reduced graphene oxide (RGO) and graphene nanoribbons (GNRs) as infrared photodetectors is explored, based on recent results dealing with solar cells, light-emitting devices, photodetectors, and ultrafast lasers. IR detection is demonstrated by both RGO and GNRs in terms of the time-resolved photocurrent and photoresponse. The responsivity of the detectors and their functioning are presented.

Negative differential resistance in GaN nanocrystals above room temperature.

Negative differential resistance (NDR) has been observed for the first time above room temperature in gallium nitride nanocrystals synthesized by a simple chemical route. Current-voltage characteristics have been used to investigate this effect through a metal-semiconductor-metal (M-S-M) configuration on SiO2. The NDR effect is reversible and reproducible through many cycles.