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The authors propose a method to obtain the multifunctional spintronic device by investigating the spin-resolved transport characteristics of zigzag SiC nanoribbon (zSiCNR) heterojunction via edge asymmetric dual-hydrogenation. The spin-resolved band structures show that the dual-hydrogenation on edge C or Si atoms all can change the initial metallicity of the pristine zSiCNR with the edge mono-hydrogenation to semiconductor in the presence of ferromagnetic field. The spin-resolved current-voltage characteristics of the zSiCNR heterojunction can show spin current rectification in the same rectify direction under the parallel magnetic field. The up-spin rectification ratio of our junction can be close to 1013 at −0.5 V, which is much larger than rectification ratios of the previous junctions induced by the anti-parallel magnetic field. The zSiCNR heterojunction also exhibits a perfect spin filtering behavior with 100% spin filtering efficiency in both positive and negative bias regions under the anti-parallel magnetic field. More interestingly, the magnetoresistance is achieved by manipulating the external magnetic field in our zSiCNR heterojunction with the giant magnetoresistance ratio 5000% at 0.5 V. Therefore, the zSiCNR heterojunction via edge asymmetric dual-hydrogenation can be designed into the multifunctional spintronic devices, which has broad application prospects in the field of future spintronics. • Zigzag silicon carbon nanoribbon has potential in spin devices. • Giant spin current rectification is obtained in the presence of a ferromagnetic field. • Maximum spin current rectification ratios is closing to 1013. • Perfect spin filtering and magnetoresistance behaviors are also obtained. [ABSTRACT FROM AUTHOR]

Ti 2 Cu, TiCu and TiCu 4 were synthesized and their electrocatalytic activities for hydrogen evolution reaction (HER) were investigated. The hydrogen overpotential observed at 10 mA/ cm2 (η 10) followed the order Ti 2 Cu (η 10 = −215 mV) > TiCu (η 10 = −182 mV) > TiCu 4 (η 10 = −170 mV). The hydrogen adsorption energy (∆G Had) on Cu site of TiCu 4 is exergonic and close to optimal position (i.e. ∆G Had = 0). A synergistic effect was proposed to account for the excellent HER performance of these Ti Cu binary intermetallics compounds that could replace PGM and achieve Midas touch in the future. [Display omitted] • High purity of Ti 2 Cu, TiCu and TiCu 4 were synthesized by using rapid arc-melting technique. • Hydrogen evolution reaction (HER) study on Ti 2 Cu, TiCu and TiCu 4 in alkaline media. • HER activity of Ti 2 Cu, TiCu and TiCu 4 were explored by using density functional theory. • Synergistic effect for these Ti Cu binary intermetallics toward HER activity was discussed. [ABSTRACT FROM AUTHOR]

Sunlight-driven electrolytic splitting of water is a promising route to hydrogen production, and widespread implementation has called for the development of inexpensive, robust and large-scale electrodes. Here, nickel nanoparticles partially embedded into carbon fiber cloth (NiΦCFC) is prepared on a large scale (e.g., 40 cm × 40 cm) via a metal-mediated pitting process, which is adopted to fabricate hydrogen evolution reaction electrode for the first time. The partially embedded structure is beneficial for regulating the electron density state of carbon, exposing the nickel catalytic sites and improving the catalytic stability. The two kinds of electrochemical area and density functional theory results confirm that the interface effect between nickel and defective carbon leads into a low Gibbs free energy of H* adsorption. The NiΦCFC as flexible and efficient electrodes require a small overpotential of 131.5 mV to achieve −10 mA cm −2 . Note that the two-electrode electrolyzer composed of FeNi layered double hydroxide loaded on CFC (NiFe-LDH/CFC) (+)//NiΦCFC (−) possesses a voltage of 1.54 V at −10 mA cm −2 , which can also be powered by a solar cell. The facile and large-scale preparation of NiΦCFC as flexible electrodes could be adapted for the industrial hydrogen production powered by solar energy. [ABSTRACT FROM AUTHOR]

Two novel ferrocene-containing macrocyclic triazoles ( L1 and L2 ) and their acyclic analogs ( L3 and L4 ) were easily prepared by “click” reaction. The anions binding abilities of L1 – L4 were evaluated by cyclic voltammetry and differential pulse voltammetry methods. The results revealed that the receptors L1 – L4 have exclusive electrochemical sensing of H 2 PO 4 − , with the shift in redox potentials of L1 – L4 towards the cathodic values. The binding mechanisms between the receptors and H 2 PO 4 − were examined by 1 H NMR titrations and density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

• Metallic Ni 3 Mo 3 N porous microrods showed a low overpotential of 44.6 mV to attain a current density of 10 mA cm−2 and superstability at a large current density of 1100 mA cm−2 for 50 h. • Density functional theory (DFT) calculations clarified that the Ni 3 Mo 3 N electrocatalyst possesses various HER catalytic active sites with suitable ΔG H* values (more than ten sites) due to the metallic semiconductor structure with special electronic structure. • The constructed NC/Ni 3 Mo 3 N/NF||NiMoO 4 ·xH 2 O/NF only needed a voltage of 1.58 V to attain a current density of 50 mA cm−2, which was better than that of 20 wt% Pt/C||RuO 2 (1.71 V), and has high potential for large-scale industrial applications. The low onset potential and large current density of electrocatalysts has always been important target for hydrogen evolution reaction (HER). In especial, the large current density (larger than 1000 mA cm−2) is an important criterion for the evaluation of electrocatalysts for industrial application. Usually, the number of catalytic sites in electrocatalyst limits the current density for HER. To overcome these problems, bimetallic nitride is controllably synthesized, and the corresponding catalytic sites are regulated by a bimetallic effect. Herein, an inexpensive electrocatalyst consisting of N-doped carbon-coated porous Ni 3 Mo 3 N microrods (NC/Ni 3 Mo 3 N/NF) is cultured on nickel foam using a hydrothermal reaction and subsequent nitriding process. The designed electrocatalyst consisting of porous NC/Ni 3 Mo 3 N microrods displays efficient catalytic activity for hydrogen evolution reaction (HER), with a small overpotential of 136 mV to achieve a cathodic current density of 100 mA cm−2. Density functional theory (DFT) calculations clarified that the Ni 3 Mo 3 N electrocatalyst possesses various HER catalytic active sites with suitable ΔG H* values (more than ten sites) due to the metallic semiconductor structure with special electronic structure. It is important that NC/Ni 3 Mo 3 N/NF possess perfect superstability for HER, with a large current density of 1100 mA cm−2 for 50 h. Lastly, NC/Ni 3 Mo 3 N/NF and NiMoO 4 ·xH 2 O/NF are hired as the cathode and anode, respectively, to assemble the two-electrode electrolytic cell, thereby achieving excellent overall water splitting performance with a voltage of 1.58 V at 50 mA cm−2 in 1 M KOH aqueous solution. [ABSTRACT FROM AUTHOR]

• Fe-polyoxometalate decorated Bi 2 MoO 6 with dominant {0 1 0} facets was fabricated. • Fe-POM/BMO maintained high photo-Fenton activity in a wide pH range of 3.0–11.0. • Synergistic effect of oxygen vacancies and Fe3+/Fe2+ boosted photo-Fenton activity. • Degradation pathways and ecotoxicity of TC degradation were evaluated. It remains challenging to rationally design ultra-efficient and reusable heterogeneous photo-Fenton catalysts with a wide pH working range for environmental remediation. Here, Fe-polyoxometalate (Fe-POM)-modified Bi 2 MoO 6 with dominant {0 1 0} facets, denoted as Fe-POM/BMO, was elaborately designed and synthesized for the degradation of typical antibiotics. Benefiting from the synergistic effect of oxygen vacancies and the Fe3+/Fe2+ redox couple, the Fe-POM/BMO heterojunctions exhibited remarkable photo-Fenton degradation performance at a wide pH range of 3.0–11.0. Based on the density functional theory calculations and intermediates analysis, the probable degradation pathways of TC were unraveled. In addition, the QSAR prediction and the Microtox test (Photobacterium phoshoreum T3 spp. as the luminescent bacteria) proved that the degradation process of tetracycline could effectively alleviate the ecotoxicity. According to the findings, the application of Fe-POM/BMO in the photo-Fenton degradation process of antibiotics is eco-friendly and exhibits high application potential in environmental remediation. [ABSTRACT FROM AUTHOR]

Density functional theory calculations have been performed to systematically investigate the structural and electronic properties of neutral and anionic Ag n S m (2≤ n + m ≤6) clusters. The results show that the ground-state structures of neutral clusters are different from those of anionic clusters. Theoretical electron detachment energies (both vertical and adiabatic) are compared with the experimental measurements to verify the ground states of silver–sulfur clusters obtained in the present study. For both neutral and anionic systems, the highest occupied-lowest unoccupied molecular orbital energy gaps exhibit an odd–even oscillation as a function of the cluster size. In addition, the natural population analysis reveals that the charges transfer from Ag atoms to S atoms in Ag n S m clusters, and the extra electron of Ag n S m − clusters is mainly localized on the 3p subshells of S atoms. [ABSTRACT FROM AUTHOR]

A self-assembled iron(II) phthalocyanine single layer adsorbed on the topological insulator Bi2Te3 was investigated by spin-polarized scanning tunneling microscopy and density functional theory calculations. Although the molecule-substrate interaction is dominated by a relatively weak van der Waals force, the local density of states of Fe was found to strongly depend on the adsorption sites, resulting in a supermolecular lattice. Spin-polarized measurements show that the magnetic moment of iron(II) phthalocyanine persists with an in-plane magnetic easy axis, which was fürther confirmed by density functional calculations. [ABSTRACT FROM AUTHOR]