Excitonic solar cells based on van der Waals heterojunctions of Janus III-VI chalcogenide monolayers.

We construct the two-dimensional (2D) excitonic solar cells based on type II vdW heterojunctions of Janus III-VI chalcogenide monolayers and investigate the performance of the device using the first principle. The calculated solar energy absorbance of InSSe/GaInSeand InSeTe/GaInSeheterojunctions is the order of 10cm. The predicted photoelectric conversion efficiency of the InSeTe/GaInSeheterojunction can reach up to 24.

Field-Created Coordinate Cation Bridges Enable Conductance Modulation and Artificial Synapse within Metal Nanoparticles.

When metal nanoparticles are functionalized with charged ligands, the movement of counterions and conduction electrons is coupled, which enables us to develop electronic devices, including diodes, transistors, and logic gates, but dynamically modulating the conductivity of a synaptic device within these materials has proved challenging. Here we show that an artificial synapse can be created from thin films of functionalized metal nanoparticles using an active silver electrode. The electric-field-injected Ag coordinates with carboxyl ligands that sets up a conduction bridge to increase the nanoparticle conductivity by reducing the electron tunneling/hopping energy barriers.

The in-plane metal contacted 5.1 nm Janus WSSe Schottky barrier field-effect transistors.

Edge contact between two-dimensional materials and metal can achieve small contact resistance because of strong interaction. In this work, we investigated the electronic transport of in-plane (IP) heterojunctions based on Ti/WSSe and Sn/WSSe using first principle calculations. The results showed that the interface bonding and metallization are found on the IP Ti/WSSe and Sn/WSSe contact interface, indicating that the Ohmic contacts are formed between Ti, Sn and WSSe.

Enhanced performance of high Al-content AlGaN MSM photodetectors by electrode modification using hexadecanethiol.

A metal electrode modification process for AlGaN-based metal-semiconductor-metal (MSM) photodetectors have been introduced to enhance the response of solar-blind ultraviolet (UV) light detection. The hexadecanethiol organic molecules are chemically adsorbed on the electrodes of high-Al-content AlGaN MSM solar-blind UV photodetectors, which can reduce the work function of the metal electrode and change the height of the Schottky barrier. This modification process significantly increases the photocurrent and responsivity of the device compared with the referential photodetector without modification.

The effect of different covalent bond connections and doping on transport properties of planar graphene/MoS/graphene heterojunctions.

The electronic transport properties of in-plane graphene/MoS/graphene heterojunctions are studied using density functional theory and the nonequilibrium Green's function method. It is found that different covalent bond connections cause different electron distributions, such as accumulation or depletion, on the contact surface. The C-S structure exhibits more electron accumulation and depletion, indicating that the electrons can easily transfer from MoS to graphene.