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In this paper, a novel Pt/CoP/C photo-electro synergistic catalyst was successfully synthesized by a hydrothermal method combined with phosphorus doping treatment. The addition of Vulcan XC-72R is in favor of effectively preventing agglomeration of active catalytic sites, resulting in more uniform and smaller Pt and CoP nanoparticles. The as-obtained Pt/CoP/C shows excellent photo-electro catalytic performance for the HER with simulated solar light irradiation. The optimal hydrogen production is 5384.18 mmol h−1 g−1, which is obviously higher than that of the commercial catalyst (20 wt% Pt/C: 4608.52 mmol h−1 g−1). The research results show that introducing cobalt phosphide into the Pt catalyst can improve the electrocatalytic activity and stability for the HER; in particular, the existence of Co3O4 in Pt/CoP/C leads to an efficient photo-electro catalysis under irradiation, which significantly improves the catalytic activity of Pt. The results above provide a novel strategy for the rational design of cost-effective Pt-based composites towards a fast HER. [ABSTRACT FROM AUTHOR]

The Cu-In 2 O 3 /C nanocomposite prepared by a simple solid-phase reduction exhibits highly selective electrocatalytic activity for reduction of CO 2 to CO with Faraday efficiency (86.7%) at −0.48 V vs. RHE, as well as large current densities (55 mA cm−2) under low overpotentials (−1.08 V vs. RHE) and good stability in electrocatalytic reduction of CO 2. Meanwhile, it is found that the tunable syngas formation can be obtained by rationally adjusting the applied potential using the Cu-In 2 O 3 /C nanocomposite as an electrocatalyst. • The Cu-In 2 O 3 /C composite was prepared by a simple solid-phase reduction method. • Cu-In 2 O 3 /C exhibits highly selective catalytic activity for reduction of CO 2 to CO. • The tunable syngas can be obtained on Cu-In 2 O 3 /C by adjusting the applied potential. The Cu-In 2 O 3 /C nanocomposite was prepared by a simple solid-phase reduction method. The introduction of In 2 O 3 into Cu/C to form the Cu-In 2 O 3 /C nanocomposite evidently enhances the electrocatalytic activity for the selective reduction of CO 2 to CO. Specifically, the Cu-In 2 O 3 /C nanocomposite exhibits higher Faraday efficiency (FE = 86.7%) at −0.48 V vs. the reversible hydrogen electrode (RHE) in the electrocatalytic reduction of CO 2 to CO and larger current densities (55 mA cm−2) under a low overpotential (−1.08 V vs. RHE). These indicate its superior performance over many of the reported Cu-based catalysts [1–4]. It was also found that by rationally adjusting the applied potential, tunable syngas can be formed, which can be used to synthesize formic acid, methyl ether, methanol, synthetic fuels, or other bulk chemicals through appropriate industrial processes. Furthermore, the Cu-In 2 O 3 /C nanocomposite maintains good stability in the electrocatalytic reduction of CO 2. This work demonstrates a novel strategy to convert CO 2 into desired products with high energy efficiency and large current density under low overpotential by the rational designing of non-precious metal catalysts. [ABSTRACT FROM AUTHOR]

A potential non-noble metal oxide catalyst with its low-cost and efficient catalytic ability attract increasing attention. In this paper, a highly efficient bifunctional electrocatalyst Co||MnCo 2 O 4.5 /NC with heterostructure and oxygen vacancies is prepared utilizing solid reaction in-situ. The optimal catalyst is obtained at 650 °C with the mass ratio (1:8) of MnCo 2 O 4.5 and Dicyandiamide (DCD). It shows excellent electrocatalytic activity for oxygen reduction reaction (ORR) with high half-wave potential (0.81 V) and limit current density (6.22 mA cm−2), which is better than that of the commercial 20% Pt/C(0.81 V, 5.52 mA cm−2). At the same time, it also exhibits superior electrocatalytic activity for oxygen evolution reaction (OER) with low overpotential (330 mV) and a faster dynamics process. The superior electrocatalytic properties may be resulted from the presence of heterostructure and increasing ratio of oxygen vacancies, which helps to the rapid transfer of electrons and creates more active sites. Moreover, the self-generated N-doped carbon provides high conductivity of the as-prepared Co||MnCo 2 O 4.5 /NC composite. It can be seen that the application of interface engineering technologies is useful for improving the performance of the catalyst, providing an effective and facile synthesis strategy for non-noble metal catalyst. • The Co||MnCo 2 O 4.5 /NC was prepared based on spinel MnCo 2 O 4.5 using solid phase reaction in situ. • The Co||MnCo 2 O 4.5 /NC has the dual characteristic of the heterostructure and more oxygen vacancies. • The Co||MnCo 2 O 4.5 /NC presents excellent difunctional electrocatalytic properties toward ORR and OER. • The zinc-air battery using Co||MnCo 2 O 4.5 /NC as a catalyst shows outstanding energy density and extraordinary stability. [ABSTRACT FROM AUTHOR]

A novel chain coordination polymer {[Cd 2 (H 2 O) (C 6 H 4 NO 2) 3 (C 12 H 8 N 2) 2 [TaF 6 } n (1) [(C 6 H 4 NO 2)−: 3-pyridinecarboxylate, C 12 H 8 N 2 : 1,10-phenanthroline (phen)] was prepared successfully by two-step solvothermal synthesis. The compound has been structurally characterized by elemental analysis, IR spectrum and X-ray single-crystal diffraction. In the titled compound, each Cd2+ cation adopts two O atoms from one 3-pyridinecarboxylate ligand, two N atoms from one phen ligand and two N atoms from two different 3-pyridinecarboxylate ligands to generate a slightly distorted octahedron. Neighboring two Cd2+ cations are linked by one N atom and one O atom from the same carboxylate group with the Cd⋯Cd distance of 8.520 Å. The dinuclear fragment is further extended into a 1-D infinite chain structure through N atoms and O atoms from carboxylate groups. The neighboring chains are interconnected into a three-dimensional supramolecular network by means of three types of hydrogen bonds O1(water)–H···O, C–H⋯O and C–H⋯F. In addition, the fluorescence excitation and emission spectra, quantum yield and decay lifetime of the compound have been also studied in this text. A novel Cd (Ⅱ) coordination polymer prepared by two-step solvothermal synthesis exhibits an interesting one-dimensional chain structure containing four-membered rings and features the first Cd (Ⅱ) chain coordination polymer containing [TaF 6 - anion. In the compound there exists a three-dimensional supramolecular network structure and exhibits green emission with the quantum yield of 26.62% and the decay lifetime of 3.66 ns. Image 1 • A novel Cd (II) coordination polymer was prepared by two-step solvothermal synthesis. • The compound contains two kinds of ligands and [TaF 6 - anion. • The compound exhibits one-dimensional chain structure containing 4-MRs. • The chains are interconnected into a three-dimensional supramolecular network. • The compound exhibits green emission with high luminescence efficiency. [ABSTRACT FROM AUTHOR]

A fast islanding detection tool can help power dispatchers monitor and control power system operations. Frequency monitoring network (FNET) is a low cost and quickly deployable wide-area phasor measurement system at the distribution system level. The frequency disturbance recorder (FDR) in FNET is actually a single-phase phasor measurement unit (PMU) installed at ordinary 120 V outlets in the sense that it measures the voltage phase angle, amplitude, and frequency from a single-phase voltage source. Based on the data collected by the FDRs deployed in the North American power grid, two islanding detection methods, the frequency difference method and the change of angle difference method, are proposed. The nine real cases recorded, including islanding cases, generation trip cases, load shedding cases and oscillation cases, are presented to verify the proposed methods of islanding detection. Sensitivity analysis on the thresholds of the frequency deviation and angle deviation is done based on the real measurement data for obtaining the insensitive interval of two thresholds. The results show that the proposed methods can correctly detect power system islanding, and will not be falsely triggered by generation trips, load shedding and system oscillations. [ABSTRACT FROM PUBLISHER]

In this work, a one-pot solid phase reaction was used to synthesize PtIn/3D-GNs composites with different alloying degrees. The as-synthesized composites were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and X-ray photoelectron spectroscopy (XPS). The results indicate that PtIn alloy was formed in the PtIn/3D-GNs composites. However, In(0) content in the composites (denoted as PtIn/3D-GNs (O)) when In2O3 was used as a precursor of In is almost twice as much as that in the composites (denoted as PtIn/3D-GNs (S)) using In(NO3)3 as a precursor of In, which indicates the higher Pt–In alloying degree in PtIn/3D-GNs (O). Electrochemical tests show that PtIn/3D-GNs composites exhibit superior electrocatalytic activity, better stability and enhanced antipoisoning ability toward methanol oxidation reaction (MOR) in comparison with Pt/3D-GNs and the commercial Pt/C. Interestingly, the synergistic effect between the charge separation of In2O3 and the SPR excitation of In(0) under light irradiation contributes to their good electro-photocatalytic performance under simulated sunlight irradiation. Especially, the higher Pt–In alloying degree in PtIn/3D-GNs (O) contributes to its better conductivity, which is responsible for its more efficient electro-photocatalytic properties. [ABSTRACT FROM AUTHOR]