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Zn-Co(OH)2 precursor was hydrothermally deposited on carbon paper at 120°C, using cobalt nitrate and zinc nitrate as raw materials. Then Zn-Co(OH)2 was etched and partially sulfided into CoSOH/Co(OH)2 with 5 mol/L NaOH and 1 mol/L Na2S aqueous solution at room temperature. The catalytic performance in oxygen evolution reaction (OER) was investigated. XRD, SEM, TEM, XPS were used to characterize the microstructure, physical and chemical properties of the catalyst. The results show that the used method can etch Zn atoms, create oxygen vacancies and dope sulfur. The oxygen vacancies and doped sulfur play a positive role in enhancing the OER performance. In addition, amorphous CoSOH also exhibited better OER activity. The synergy between CoSOH and Co(OH)2 finally induces the best catalytic properties (overpotential η=310 mV, Tafel slope b=90 mV/dec) and long-term electrochemical stability, that is CoSOH/Co(OH)2 possess superior electrocatalytic oxygen evolution performance.

With H2WO4 and EDA as precursors, WO3/C intermediate is obtained by mechanical stirring and in-situ solid-phase pyrolysis, then WS2/C composite material is obtained by high temperature vulcanization. The WS2/C composite is characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and other instrumental analysis methods. At the same time, the electrocatalytic performance of the catalyst was analyzed by the electrocatalytic steady-state polarization curve (LSV), Tafel slope (Tafel), cycle stability (CP), electrochemical impedance (PEIS) and Electrochemically Active Surface Area (ECSA) tests of the material. The results showed that when the current density of the WS2/C composite is 10 mA/cm2, overpotential is 179 mV, and Tafel slope is 98 mV/dec.

A novel amorphous FeOOH modified BiVO4 photocatalyst (A-FeOOH/BiVO4) was successfully produced and characterized by various techniques. The results showed that amorphous FeOOH with about 2 nm thickness evenly covered on BiVO4 surface, which caused resultant A-FeOOH/BiVO4 exhibiting higher visible light photocatalytic performance for producing O2 from water than BiVO4. When the covered amount of amorphous FeOOH was 8%, the resultant photocatalyst possessed the best photocatalytic performance. To find the reasons for the improvement of photocatalytic property, electrochemical experiments, DRS, PL and BET, were also measured, the experimental results indicated that interface effect between amorphous FeOOH and BiVO4 could conduce to migration of photogenerated charge, and exhibit stronger light responded capacity. These positive factors promoted A-FeOOH/BiVO4 presenting improved the photocatalytic performance. In a word, the combination of amorphous FeOOH with BiVO4 is an effective strategy to conquer important challenges in photocatalysis field.

Ternary MoS2/MoO3/C nanosheets were successfully synthesized via a chemical vapor deposition method. The hybrids were characterized by x-ray diffraction, scanning electron microscope, high-resolution transmission electron microscopy, raman and x-ray photoelectron spectroscopic methods. The as-obtained MoS2/MoO3/C nanosheets applied as an anode material for lithium-ion batteries, showed high initial discharge/charge capacities at current rates of 0.5C, 1640.9 mA h g−1 and 1393.8 mA h g−1 respectively, with initial coulombic efficiency of approximately 84.9%. The material exhibited superior rate capabilities, with specific discharge capacities of 1240.2 mA h g−1, 1048.5 mA h g−1, 917.2 mA h g−1, 742.3 mA h g−1, 663.6 mA h g−1, 601.8 mA h g−1 and 593.4 mA h g−1 at current rates of 0.2C, 0.4C, 1C, 4C, 8C, 12C and 15C, respectively. This superior electrochemical performance was mainly due to the uniformly-distributed MoS2 nanosheets and to highly graphitized carbon, which not only mitigated mechanical stress during repeated cycling, but also provided good conductivity.

A higher magnetic field can provide more opportunities to reveal new phenomena in a scientific research. Aiming to achieve a higher magnetic field, Wuhan National High Magnetic Field Center (WHMFC), Wuhan, China has designed a a power supply system for 100 T magnetic field under existing power supply conditions in April 2015. The 100 T magnet consisting of three coils is energized by a multipower supply system. The outer coil is energized by a pulsed generator-rectifier connected to battery bank in series. The middle coil and the inner coil are energized by two capacitor bank, respectively. To ensure safety and reliable operation, control sequence as well as protection system for the power system is designed and developed. A test system including the prototype of three-coil magnet is established at WHMFC. A series of tests are carried out on hybrid power supply systems. 73.3 T peak field has been achieved as the highest magnetic field in the test. The test results presented in this paper show the hybrid power supply system is feasible and operable.

High pulsed magnetic field is becoming widely used in physics, biology, and materials. For better performance of scientific experiments, a power supply system for 100 T magnetic field is designed at Wuhan National High Magnetic Field Center. In the preliminary design, the 100 T magnet consists of three coils in a coaxial structure. Because of the multicoil system with strong-coupling structure, the current of the outer coil will drop when the middle coil is fired. And the current drop will cause adverse effects, which increase the burden of power supply and the stress of magnet. Based on the analysis of the mathematical model for power supply circuit, this paper proposes a modified design for power supply system, which is an auxiliary power supply connected in series with primary power supply of the outer coil for the compensation of the current drop. Corresponding parameters, circuit topology, and control strategy of capacitors are also discussed. The simulation results of the modified design of power supply system are presented in this paper.

A quasi-continuous high magnetic field is a special kind of pulsed magnetic field with a flat-top field longer than 100 ms. This paper proposes a hybrid power supply that consists of a capacitor power supply and a generator–rectifier power supply. A dual-coil magnet is powered to generate a 65 T/100 ms quasi-continuous high magnetic field with a ripple less than 500 ppm at the Wuhan National High Magnetic Field Center, Wuhan, China. A protection circuit consists of an R-C branch and a diode array is discussed for the worst short-circuit fault, which occurs between the first turns of inner coil and outer coil. This type of fault will produce oscillation voltage with a high peak value and high frequency on the rectifiers. A self-adaptive PI controller with the coefficients corrected by a back propagation neural network is adopted to reduce the ripple of a flat-top.

MoS 2 /C nanocomposite with a multilayered sandwich structure based on few-layered MoS 2 and carbon layers in an alternating sequence, was successfully synthesized through a one-step synchronized carbonization and sulfuration method. The hybrids were characterized by X-ray diffraction, High-resolution transmission electron microscopy, Atomic force microscope, Raman and X-ray photoelectron spectroscopic methods. The as-obtained MoS 2 /C nanocomposite applied as lithium-ion batteries anode materials, showed a high initial discharge and charge capacities of 1678.5 and 1386.0 mAh g −1 , respectively. High specific reversible capacity is maintained at fast C rates, e.g., 1390, 1223, 1017, 566, and 450 mAh g −1 at 0.1C, 0.6C, 3C, 10C and 20C, respectively. The good performance of the composite is mainly attributed to the unique few layered composite architectures, which can improve ion/electron transportation and prevent aggregation and restacking during the lithiation/delithiation process.

A multi-layer-cake WS2/C nanocomposite was successfully synthesized via an intercalation-transformation method, in which few-layered WS2 and carbon were sandwiched in an alternating sequence. As a benefit of the electronic conductivity enhanced by the interlayer carbon and the unique "regular" and "alternate" architecture, the WS2/C nanocomposite showed promising performance as anode material for lithium-ion batteries. The nanocomposite demonstrated a high capacity of 829.4 mAhg-1 at 0.3 Ag-1 after 140 cycles and it could still deliver a stable capacity of about 326.8 mAhg-1 at a current density of 8.0 Ag-1.

A four-angle star-like Co–Al mixed metal oxide (CoAl-MMO)/BiVO4 heterojunction has been synthesized via a hydrothermal method and following sintering. The CoAl-MMO/BiVO4 is derived from CoAl-LDHs/BiVO4, in which CoAl-LDHs leads to a distribution of amorphous CoAl-MMO. The CoAl-MMO loading on BiVO4 greatly enhances visible light absorption, improves charge separation by band offset charge transfer, and makes flat band potential more negative. The three effects together result in excellent photocatalytic activity. Under visible light irradiation, desulfurization efficiency of thiophene has achieved up to 98.58% on CoAl-MMO/BiVO4 with molar ratio of 0.3 : 5.

Hydrothermal synthesis is a typical method for the preparation of TS-1. In the current study, agitation was introduced during the crystallisation stage, and nano-sized TS-1 with little anatase TiO2 was successfully synthesised in a short time (1–8 h). Furthermore, under rotational crystallisation conditions, a series of TS-1 samples was prepared with different crystallisation times, and the products obtained were investigated as catalysts for the oxidative desulfurisation of thiophene from a model fuel. All samples were characterised utilising X-ray diffraction (XRD), scanning electron microscopy (SEM), N2-adsorption, ultraviolet-visible (UV-Vis) spectroscopy and Fourier-transform infrared (FT-IR) spectroscopy techniques. It was found that under rotational crystallisation conditions, nano-sized TS-1 could be synthesised in a short time that had improved efficiency for the oxidative desulfurisation reaction of thiophene in comparison with TS-1 synthesised by static crystallisation for 24 h.

An optimal and adaptive control strategy for the flat-top long-pulse magnet system of single or dual coaxially nested coils is proposed and designed in this paper. By integrating a voltage feedback control loop and an adaptive feedforward compensation algorithm in the conventional current control configuration, the magnet system's dynamic field response could be further improved with little field overshoot and low-frequency oscillation. For the identification of the long-pulse magnets' dynamically varying resistance needed for the compensation loop in the proposed control strategy, a novel computation method employing the gradient descent technique is presented in details. Simulation results in generating high flat-top low ripple pulsed field are presented comprehensively to validate the good dynamic performance of the adopted new controller and the feasibility of the online computation model.

High magnetic field is one of the most significant tools for scientific experiments. To obtain higher magnetic field, a nondestructive magnet aimed at generating 100 T, which achieves the best utilization of the power supplies at the Wuhan National High Magnetic Field Center, is designed. This magnet will make up of three coils nested coaxially. The inner coil and the middle coil will be energized by two independent capacitor banks, respectively, and the outer coil will be powered using the combined power supply of battery bank and power converter modules energized by a 100-MVA/185-MJ generator. During operation of magnet and power supplies, a proper procedure is needed to ensure the achievement of 100 T and system safety. A new protection system is needed to avoid damage to the power supplies. The configuration of the power supplies for the first 100-T nondestructive magnet and control strategy and protection system for the power supplies are described in this paper. Digital simulation results of the power supplies are present also.

The controlled pulsed high magnetic field can promote some scientific research effectively such as nuclear magnetic resonance imaging, terahertz, etc. Hence, in this paper, a multipulse high-magnetic-field system is designed by a 100-MVA/100-MJ generator at the Wuhan High Magnetic Field Center. In this system, to improve the energy utilization rate, the storage energy of the magnet would be fed back to the flywheel after each discharge shot by the 4-quadrant 12-pulse thyristor rectifier. Consideration of the difficulties of phase jump, commutation notch, varied frequency, and distorted output voltage of the generator, a novel phase-locked loop (PLL) based on the genetic algorithm (GA) is proposed. This GA PLL can not only help avoid the problem of the invert fault but also improve the accuracy of the firing angles. On the base of exact firing, a combined closed-loop with forward-feed control system is designed, which could achieve fast response and steady accuracy at the same time. The simulations and the experiments verified the feasibility of the design, and accordingly, a 5/10/15/20-T multistage pulse and 20-T multipulse are generated.

Specific surface area, hierarchical porosity and heteroatom doping have been proved to be desirable for carbon electrode materials in advanced super-capacitors. In this study, homogeneous sulphur-doped porous carbon materials (L-HPCs) with a unique hierarchical porous nanostructure have been prepared by the combination of the two-dimensional interlayer confinement effect of a layered double hydroxide (LDH) and KOH activation method. XRD, SEM, TEM, BET, EIS, cyclic voltammetry and the constant current charge–discharge test were used to investigate the morphology, structure, surface properties and electrochemical performances of the carbon materials. The L-HPCs fabricated by this method have a large specific surface area of 2154.0 m2 g−1 and contain plenty of micropores and mesopores, which arise from the carbonisation of organic polymers, the presence of LDH and the catalytic effect of iron in LDH layers in the calcination process. The L-HPCs serving as an electrode material for super-capacitors exhibited a specific capacitance as high as 259 F g−1 at 1 A g−1 in 6 M KOH electrolyte. This excellent electrochemical performance might be due to the high surface area, high pore volume and hierarchical porous structure of the carbon materials, which provide a quick ion transfer pathway to electrolyte access into the microporous area. At the same time, the doping of heteroatoms can improve the conductivity of the electrode materials.

Layered LiCo1/3Ni1/3Mn1/3O2 has been modified with Co–Al-mixed metal oxide (CoAl-MMO). The surface-modified materials were characterized by X-ray diffraction, field emission scanning electron microscopy, and galvanostatic charge–discharge cycling. The CoAl-MMO-coated LiCo1/3Ni1/3Mn1/3O2 had an initial discharge specific capacity of 178.1 mAh g−1 within the potential range of 2.75–4.5 V (vs. Li+/Li), and its discharge specific capacity is 175.0 mAh g−1 after 50 cycles, much higher than that of the pristine LiCo1/3Ni1/3Mn1/3O2 (148.4 mAh g−1). The improvement could be attributed to the CoAl-MMO coating layer that would hinder interaction between LiCo1/3Ni1/3Mn1/3O2 and electrolyte and stabilize the structure of LiCo1/3Ni1/3Mn1/3O2. Moreover, DSC showed that the CoAl-MMO-coated LiCo1/3Ni1/3Mn1/3O2 had a higher thermal stability than the pristine LiCo1/3Ni1/3Mn1/3O2. Therefore, the CoAl-MMO-coated LiCo1/3Ni1/3Mn1/3O2 could be a high-performance cathode material for lithium-ion batteries.