CO-Assisted Controllable Synthesis of PdNi Nanoalloys for Highly Selective Hydrogenation of Biomass-Derived 5-Hydroxymethylfurfural.

The selective hydrogenation of 5-hydroxymethylfurfural (HMF) to 2,5-bishydroxymethyltetrahydrofuran (BHMTHF), a vital fuel precursor and solvent, is crucial for biomass refining. Herein, we report highly selective and stable PdNi nanoalloy catalysts for this deep hydrogenation process. A CO-assisted green method was developed for the controllable synthesis of various bimetallic and monometallic catalysts.

A Rechargeable Urea-Assisted Zn-Air Battery With High Energy Efficiency and Fast-Charging Enabled by Engineering High-Energy Interfacial Structures.

Electrochemical urea oxidation reaction (UOR) offers a promising alternative to the oxygen evolution reaction (OER) in clean energy conversion and storage systems. Nickel-based catalysts are regarded as highly promising electrocatalysts for the UOR. However, their effectiveness is significantly hindered by the unavoidable self-oxidation reaction of nickel species during UOR.

Superconductivity in the High-Entropy Ceramics Ti Zr Nb Mo Ta C with Possible Nontrivial Band Topology.

Topological superconductors have drawn significant interest from the scientific community due to the accompanying Majorana fermions. Here, the discovery of electronic structure and superconductivity (SC) in high-entropy ceramics Ti Zr Nb Mo Ta C (x = 1 and 0.8) combined with experiments and first-principles calculations is reported.

Understanding Bridging Sites and Accelerating Quantum Efficiency for Photocatalytic CO Reduction.

We report a novel double-shelled nanoboxes photocatalyst architecture with tailored interfaces that accelerate quantum efficiency for photocatalytic CO reduction reaction (CORR) via Mo-S bridging bonds sites in S-InS@2H-MoTe. The X-ray absorption near-edge structure shows that the formation of S-InS@2H-MoTe adjusts the coordination environment via interface engineering and forms Mo-S polarized sites at the interface. The interfacial dynamics and catalytic behavior are clearly revealed by ultrafast femtosecond transient absorption, time-resolved, and in situ diffuse reflectance-Infrared Fourier transform spectroscopy.

Interplay between Charge-Density-Wave, Superconductivity, and Ferromagnetism in CuIrCrTe Chalcogenides.

We report the crystal structure, charge-density-wave (CDW), superconductivity (SC), and ferromagnetism (FM) in CuIrCrTe (0 ≤ ≤ 2) chalcogenides. Powder x-ray diffraction (PXRD) results reveal that the CuIrCrTe series are distinguished between two structural types and three different regions: (i) layered trigonal structure region, (ii) mixed phase regions, and (iii) spinel structure region. Besides, Cr substitution for Ir site results in rich physical properties including the collapse of CDW, the formation of dome-shaped like SC, and the emergence of magnetism.

Superconducting dome associated with the suppression and re-emergence of charge density wave states upon sulfur substitution in CuIrTechalcogenides.

We report the path from the charge density wave (CDW)-bearing superconductor CuIrTeto the metal insulator transition (MIT)-bearing compound CuIrSby chemical alloying with the gradual substitution of S for Te. The evolution of structural and physical properties of the CuIrTeS(0 ⩽⩽ 4) polycrystalline system is systemically examined. The x-ray diffraction (XRD) results imply CuIrTeS(0 ⩽⩽ 0.

Discovery and Facile Synthesis of a New Silicon Based Family as Efficient Hydrogen Evolution Reaction Catalysts: A Computational and Experimental Investigation of Metal Monosilicides.

A new family of transition-metal monosilicides (MSi, M = Ti, Mn, Fe, Ru, Ni, Pd, Co, and Rh) electrocatalysts with superior electrocatalytic performance of hydrogen evolution is reported, based on the computational and experimental results. It is proposed that these MSi can be synthesized within several minutes by adopting the arc-melting method. The previously reported RuSi is not only fabricated more readily but eventually explored 8 MSi that can be good hydrogen evolution reaction catalysts.

Multifunctional 2H-TaS nanoflakes for efficient supercapacitors and electrocatalytic evolution of hydrogen and oxygen.

Layered transition-metal dichalcogenides based on VIB elements have attracted substantial attention for their applications in energy storage and conversion. However, few studies have concentrated on VB element dichalcogenides. Herein, we report that trifunctional 2H-TaS2 nanoflakes exhibit high performance when applied in supercapacitors, hydrogen evolution reactions (HER) and oxygen evolution reactions (OER).

NbSeTe-a new layered transition metal dichalcogenide superconductor.

Transition metal dichalcogenides (TMDCs) usually exhibit layered polytypic structures due to the weak interlayer coupling. 2H-NbSe is one of the most widely studied in the pristine TMDC family due to its high superconducting transition temperature (T   =  7.3 K) and the occurrence of a charge-density wave (CDW) order below 33 K.

Origin of Subthreshold Turn-On in Quantum-Dot Light-Emitting Diodes.

The subthreshold (or sub-bandgap) turn-on for electroluminescence is one of the most discussed, but often misinterpreted, phenomena for solution-processed quantum-dot light-emitting diodes. Here, multiple techniques are applied to show that the phenomenon can be readily explained using the fundamental rules of carrier injection and transport. Evident from temperature dependent photovoltage measurements, it is found that the energy up-conversion originating from the decay of charge transfer excitons is not responsible for the subthreshold turn-on.

Charge transfer-induced photoluminescence in ZnO nanoparticles.

The quality of solution-processed zinc oxide (ZnO) nanoparticles (NPs) is often correlated with their photoluminescence (PL) spectral characteristics. However, the reported PL spectral characteristics lack consistency and remain controversial. Here we report that "defect-emission free" PL spectra can even be obtained in thin films composed of as-synthesized ZnO NPs.

Epidemiological investigation of non-albicans Candida species recovered from mycotic mastitis of cows in Yinchuan, Ningxia of China.

Background: Candida spp. is the vital pathogen involved in mycotic mastitis of cows. However the epidemiology and infection of Candida species in mycotic mastitis of cow in Ningxia province of China has not been explored.

Global Transcriptome Changes of Biofilm-Forming Staphylococcus epidermidis Responding to Total Alkaloids of Sophorea alopecuroides.

Transcriptome changes of biofilm-forming Staphylococcus epidermidis response to total alkaloids of Sophorea alopecuroides was observed. Bioinformatic analyses were further used to compare the differential gene expression between control and the treated samples. It was found that 282 genes were differentially expressed, with 92 up-regulated and 190 down-regulated.

Endohedral gallide cluster superconductors and superconductivity in ReGa5.

We present transition metal-embedded (T@Gan) endohedral Ga-clusters as a favorable structural motif for superconductivity and develop empirical, molecule-based, electron counting rules that govern the hierarchical architectures that the clusters assume in binary phases. Among the binary T@Gan endohedral cluster systems, Mo8Ga41, Mo6Ga31, Rh2Ga9, and Ir2Ga9 are all previously known superconductors. The well-known exotic superconductor PuCoGa5 and related phases are also members of this endohedral gallide cluster family.

Superconductivity in 3R-Ta(1-x)M(x)Se2 (M = W, Mo).

The 3-layer rhombohedral (3R) polytype of TaSe2-x Te x is known to display a superconducting transition temperature that is between 6 and 17 times higher than that of the two-layer hexagonal (2H) polytype. The remarkable difference in T c, although clearly associated with a difference in polytype, could have been due to an electronic effect specific to the Te-Se substitution. Here we report that small amounts of Mo or W doping lead to a 2H to 3R polytype transition in Ta1-x Mo x Se2 and Ta1-x W x Se2.

Characterization of the heavy metal pyrochlore lattice superconductor CaIr2.

We report the electronic properties of the cubic laves phase superconductor CaIr2(Tc = 5.8 K), in which the Ir atoms have a pyrochlore lattice. The estimated superconducting parameters obtained from magnetization and specific heat measurements indicate that CaIr2 is a weakly coupled BCS superconductor.

A large family of filled skutterudites stabilized by electron count.

The Zintl concept is important in solid-state chemistry to explain how some compounds that combine electropositive and main group elements can be stable at formulas that at their simplest level do not make any sense. The electronegative elements in such compounds form a polyatomic electron-accepting molecule inside the solid, a 'polyanion', that fills its available energy states with electrons from the electropositive elements to obey fundamental electron-counting rules. Here we use this concept to discover a large family of filled skutterudites based on the group 9 transition metals Co, Rh, and Ir, the alkali, alkaline-earth, and rare-earth elements, and Sb4 polyanions.

Polytypism, polymorphism, and superconductivity in TaSe(2-x)Te(x).

Polymorphism in materials often leads to significantly different physical properties--the rutile and anatase polymorphs of TiO2 are a prime example. Polytypism is a special type of polymorphism, occurring in layered materials when the geometry of a repeating structural layer is maintained but the layer-stacking sequence of the overall crystal structure can be varied; SiC is an example of a material with many polytypes. Although polymorphs can have radically different physical properties, it is much rarer for polytypism to impact physical properties in a dramatic fashion.

A novel CO2-stable dual phase membrane with high oxygen permeability.

By cobalt-doping of the mixed conducting phase PSFC, a good combination of high CO2 stability and high oxygen permeability is obtained for the 60 wt% Ce(0.9)Pr(0.1)O(2-δ)-40 wt% Pr(0.

Natural gas to fuels and chemicals: improved methane aromatization in an oxygen-permeable membrane reactor.

Adding value with membranes: Improved methane aromatization was achieved by using an oxygen-permeable membrane. The resulting membrane reactor shows a superior methane conversion and a higher resistance towards catalyst deactivation.