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The transition metal phosphide (TMP)-based functional electrocatalysts are very promising for the development of electrochemical energy conversion and storage devices including rechargeable metal-air batteries and water electrolyzer. Tuning the electrocatalytic activity of TMPs is one of the vital steps to achieve the desired performance of these energy devices. Herein, we demonstrate the modulation of the bifunctional oxygen electrocatalytic activity of nitrogen-doped carbon-encapsulated CoP (CoP@NC) nanostructures by surface tailoring with ultralow amount (0.56 atomic %) of Ru nanoparticles (2.5 nm). The CoP at the core and the Ru nanoparticles on the shell have a facile charge transfer interaction with the encapsulating NC. The strong coupling of Ru with CoP@NC boosts the electrocatalytic performance toward oxygen reduction (ORR), oxygen evolution (OER), and hydrogen evolution (HER) reactions. The surface-tailored catalyst requires only 35 mV to deliver the benchmark current density of 10 mA·cm -2 for HER. A small potential gap of 620 mV between ORR and OER is achieved, making the catalyst highly suitable for the development of rechargeable zinc-air batteries (ZABs). The homemade ZAB delivers a specific capacity of 780 mA·hg Zn -1 and peak power density of 175 mW·cm -2 with a very small voltaic efficiency loss (1.1%) after 300 cycles. The two-electrode water splitting cell (CoP@NC-Ru||CoP@NC-Ru) delivers remarkably low cell voltage of 1.47 V at the benchmark current density. Stable current density of 25 mA·cm -2 for 25 h without any significant change is achieved. Theoretical studies support the charge transfer interaction-induced enhanced electrocatalytic activity of the surface-tailored nanostructure.

Free-space time domain THz spectroscopy accesses electrodynamic responses in a frequency regime ideally matched to interacting condensed matter systems. However, THz spectroscopy is challenging when samples are physically smaller than the diffraction limit of ∼0.5 mm, as is typical, for example, in van der Waals materials and heterostructures. Here, we present an on-chip, time-domain THz spectrometer based on semiconducting photoconductive switches with a bandwidth of 200 to 750 GHz. We measure the optical conductivity of a 7.5-μm wide NbN film across the superconducting transition, demonstrating spectroscopic signatures of the superconducting gap in a sample smaller than 2% of the Rayleigh diffraction limit. Our spectrometer features an interchangeable sample architecture, making it ideal for probing superconductivity, magnetism, and charge order in strongly correlated van der Waals materials.

The spread of the monkeypox virus has surged during the unchecked COVID-19 epidemic. The most crucial target is the viral envelope protein, p37. However, lacking p37's crystal structure is a significant hurdle to rapid therapeutic discovery and mechanism elucidation. Structural modeling and molecular dynamics (MD) of the enzyme with inhibitors reveal a cryptic pocket occluded in the unbound structure. For the first time, the inhibitor's dynamic flip from the active to the cryptic site enlightens p37's allosteric site, which squeezes the active site, impairing its function. A large force is needed for inhibitor dissociation from the allosteric site, ushering in its biological importance. In addition, hot spot residues identified at both locations and discovered drugs more potent than tecovirimat may enable even more robust inhibitor designs against p37 and accelerate the development of monkeypox therapies.

A complete process flowsheet to recover metal values from Sm 2 Co 17 -type magnet scrap was investigated. The magnet scrap was leached in chloride medium at pulp density of 2% (w/v) under the optimum conditions of 15% (v/v) HCl and 5% (v/v) H 2 O 2 at 70 °C for 3 h, which yielded 98.5% Sm and 99% Co extractions. The full factorial Design of Experiment technique was adopted for the optimization of leaching conditions. Sm was selectively separated from the leach liquor as precipitated double salt using Na 2 SO 4 . The precipitated double sulfate was later converted to Sm-oxalate, which was subsequently calcined to produce pure Sm 2 O 3 . Following Sm separation, Fe was removed through precipitation by raising the pH to 3.0. For Cu and Co recovery, solvent extraction techniques using LIX 84I and Na-CYANEX 272, respectively, were followed. The McCabe-Thiele diagrams for extraction as well as stripping were presented for both Cu and Co., Competing Interests: The authors declare no competing financial interest., (© 2020 The Authors. Published by American Chemical Society.)

The construction of functionalizable branched DNA (bDNA) relies on the designing of oligonucleotides and exploitation of their complementary chemistries. The stability of these structures largely depends on the hybridization specificity of the contributing oligonucleotides. However, most of the bDNA structures are not found suitable for in vivo application due to poor yield owing to uncharacterized hybridization efficiency and instability in biological fluids. In this report, our group has explored a mechanistic way for studying the hybridization pathway of genomic sequence derived oligonucleotides that are self-assembled to fabricate robust bDNA structures. The effect of change in nucleotide sequences on bDNA stability was studied by taking oligonucleotides derived from primers of different genes. Additionally, the stability of the bDNA in solutions with different pH, salts, and DNaseI which mimics physiological environment was reported. It was found that genomic sequence derived oligonucleotides self-assembled in a cooperative manner to yield the designed bDNAs, which are stable in physiological environment.

Herein, for the first time, we applied the metal-metal-bond-energy factor to the evolution of a porous Se-Te alloy. The porous Se-Te material has been prepared from the constituents' elemental states, through only a heating-cooling process in silicone oil without the use of any reagent, surfactant, or capping agent. Surprisingly, the reaction occurred at a much lower temperature (240 °C) than the mp (450 °C) of Te 0 . The reaction's nucleation and growth by means of varied bond energy have been clarified for the first time. A difference in the bond energies of a hetero metal-metal bond (Se-Te) and a homo metal-metal bond (Se-Se) directs nucleation and growth toward the fabrication of a porous structure, even from the constituents' elemental states, in which low-angle-grain-boundary (LAGB) and high-angle-grain-boundary (HAGB) movements play governing roles. Proper band-gap alignment of Se and Te makes the alloy composite applicable to water-splitting reactions under Xe-arc-lamp illumination. PEC efficiency of Se-Te was found to be higher than those reported for Se and other composite materials.

An efficient, cost-effective, and earth-abundant catalyst that could drive the production of hydrogen from water without or with little external energy is the ultimate goal toward hydrogen economy. Herein, nanoplates of tungsten oxide and its hydrates (WO 3 ·H 2 O) as promising electrocatalysts for the hydrogen evolution reaction (HER) are reported. The square-shaped and stacked WO 3 ·H 2 O nanoplates are synthesized at room temperature under air in ethanol only, making it as a promising green synthesis strategy. The repeated electrochemical cyclic voltammetry cycles modified the surface of WO 3 ·H 2 O nanoplates to WO 3 as confirmed by X-ray photoelectron and Auger spectroscopy, which leads to an improved HER activity. Hydrogen evolution is further achieved from distilled water (pH 5.67) producing 1 mA cm -2 at an overpotential of 15 mV versus the reversible hydrogen electrode. Moreover, WO 3 ·H 2 O and WO 3 nanoplates demonstrate excellent durability in acidic and neutral media, which is highly desirable for practical application. Improved hydrogen evolution by WO 3 (200) when compared to that by Pt(111) is further substantiated by the density functional theory calculations., Competing Interests: The authors declare no competing financial interest.

The aberrant activation of B-cells has been implicated in several types of cancers and hematological disorders. BTK and PI3Kδ are kinases responsible for B-cell signal transduction, and inhibitors of these enzymes have demonstrated clinical benefit in certain types of lymphoma. Simultaneous inhibition of these pathways could result in more robust responses or overcome resistance as observed in single agent use. We report a series of novel compounds that have low nanomolar potency against both BTK and PI3Kδ as well as acceptable PK properties that could be useful in the development of treatments against B-cell related diseases.