Silver Electrodes Are Highly Selective for CO in CO Electroreduction due to Interplay between Voltage Dependent Kinetics and Thermodynamics.

Electrochemical reduction is a promising way to make use of CO as feedstock for generating renewable fuel and valuable chemicals. Several metals can be used as the electrocatalyst to generate CO and formic acid, but hydrogen formation is an unwanted side reaction that can even be dominant. The lack of selectivity is, in general, a significant problem, but silver-based electrocatalysts have been shown to be highly selective, with faradaic efficiency of CO production exceeding 90%, when the applied voltage is below -1 V vs RHE.

Engineering the Electrical and Optical Properties of WS Monolayers via Defect Control.

Two-dimensional (2D) materials as tungsten disulphide (WS ) are rising as the ideal platform for the next generation of nanoscale devices due to the excellent electric-transport and optical properties. However, the presence of defects in the as grown samples represents one of the main limiting factors for commercial applications. At the same time, WS properties are frequently tailored by introducing impurities at specific sites.

Understanding the role of imidazolium-based ionic liquids in the electrochemical CO reduction reaction.

The development of efficient CO capture and utilization technologies driven by renewable energy sources is mandatory to reduce the impact of climate change. Herein, seven imidazolium-based ionic liquids (ILs) with different anions and cations were tested as catholytes for the CO electrocatalytic reduction to CO over Ag electrode. Relevant activity and stability, but different selectivities for CO reduction or the side H evolution were observed.

Study of Optoelectronic Features in Polar and Nonpolar Polymorphs of the Oxynitride Tin-Based Semiconductor InSnON.

In view of its potential applicability in photoconversion processes, we here discuss the optoelectronic features of the recently proposed tin-based oxynitride material for (photo)catalysis, InSnON. In detail, by combining Density Functional and Many-Body Perturbation Theory, we compute the electronic and optical properties discussing how they vary from the nonpolar phase to the more stable polar one. After providing a detailed, unbiased, description of the optoelectronic features of the two phases, we have finally calculated the Spectroscopic Limited Maximum Efficiency and obtained data that further witness the relevance of InSnON for solar energy conversion processes.

Stability and Bandgap Engineering of InGaSe Monolayer.

Bandgap engineering of semiconductor materials represents a crucial step for their employment in optoelectronics and photonics. It offers the opportunity to tailor their electronic and optical properties, increasing the degree of freedom in designing new devices and widening the range of their possible applications. Here, we report the bandgap engineering of a layered InSe monolayer, a superior electronic and optical material, by substituting In atoms with Ga atoms.

Point Defects in Two-Dimensional Indium Selenide as Tunable Single-Photon Sources.

In the past few years remarkable interest has been kindled by the development of nonclassical light sources and, in particular, of single-photon emitters (SPE), which represent fundamental building blocks for optical quantum technology. In this Letter, we analyze the stability and electronic properties of an InSe monolayer with point defects with the aim of demonstrating its applicability as an SPE. The presence of deep defect states within the InSe band gap is verified when considering substitutional defects with atoms belonging to group IV, V, and VI.

Boosted Solar Light Absorbance in PdS/PtS Vertical Heterostructures for Ultrathin Photovoltaic Devices.

Transition-metal dichalcogenides (TMDs) represent a class of materials whose archetypes, such as MoS and WS, possess exceptional electronic and optical properties and have been massively exploited in optoelectronic applications. The layered structure allows for their exfoliation to two-dimensional samples with atomic thickness (≲ 1 nm), promising for ultrathin, ultralight devices. In this work, by means of state-of-the-art many-body perturbation theory techniques, we focus on single-layer PdS and PtS and propose a novel van der Waals heterostructure with outstanding light absorbance, reaching up to 50% in the visible spectrum and yielding a maximum short-circuit current of 7.

Epidemic Threshold in Continuous-Time Evolving Networks.

Current understanding of the critical outbreak condition on temporal networks relies on approximations (time scale separation, discretization) that may bias the results. We propose a theoretical framework to compute the epidemic threshold in continuous time through the infection propagator approach. We introduce the weak commutation condition allowing the interpretation of annealed networks, activity-driven networks, and time scale separation into one formalism.