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G-C3N4 has a bright application prospect as an electrode material of supercapacitors, which makes it a concern. In order to increase the specific capacitance of g-C3N4, we consider to combine it with a metal oxide with high theoretical specific capacitance and utilize the synergistic effect. As a common metal oxide, CuO has the characteristics of high theoretical capacitance, high chemical stability, simple preparation and environmental friendliness. A composite containing CuO nanobelts and graphitic C3N4 (g-C3N4) was successfully synthesized by a chemical precipitation method. Various testing methods were used to explore its composition, microstructure and electrochemical properties to discuss whether CuO is suitable for improving the electrochemical properties of g-C3N4.

Though the concept of Berry force was proposed thirty years ago, little is known about the practical consequences of this force as far as chemical dynamics are concerned. Here, we report that when molecular dynamics pass near a conical intersection, a massive Berry force can appear as a result of even a small amount of spin-orbit coupling (, Spin polarization is at the basis of quantum information and underlies some natural processes, but many aspects still need to be explored. Here, the authors, by quantum mechanical computations, show that even a weak spin-orbit coupling near a conical intersection can induce large spin selection, with consequences for spin manipulation in photochemical or electrochemical reactions.

Commercial WS2 powders were exfoliated in sodium dodecyl sulfate solution with a combination of ball-milling and sonication. WS2 nanosheets can be uniformly dispersed in the solution. The layers and thicknesses of WS2 nanosheets could be tailored via changing the ball-milling speed. The effects of the ball-milling speed on crystallinity and morphology of the samples were analyzed. The results show that the layer structure of WS2 nanosheets is destroyed and the crystallinity is decreased with increase of the ball-milling rate. The monolayer WS2 nanosheets at 200 rpm are obtained, which are mesoporous with the specific surface area as 5.419 m2 g-1. The specific capacitance and charge/discharge efficiency of WS2 nanosheets at 200 rpm are better than those of other samples. Its specific capacitance under the scanning rate of 20 mV s-1 and the current density of 0.5 A g-1 are 13.46 F g-1 and 22.50 F g-1, respectively. The charge/discharge curve of WS2 nanosheets at 200 rpm is a symmetrical triangle, which shows rapid charge and slow discharge. It means that WS2 nanosheets at 200 rpm has good electrochemical reversibility. The load transfer resistance and the internal series resistance of this sample are 84.60 Ω and 4.18 Ω, respectively.

An automatic high-throughput computing (HTC) procedure is implemented for calculating vapor-liquid equilibrium (VLE) curves of binary systems using molecular dynamics simulation and coarse-grained force field. The HTC procedure builds simulation models, carries out the simulations, and validates the simulations automatically. The procedure is demonstrated by calculating the VLE curves for 16 binary mixtures of carbon dioxide and n-alkanes on 856 state points in the temperature range of 277.2–420.0 K and pressure range of 0.3–25.0 MPa. The averaged uncertainties in predictions are 0.119 MPa for pressure, 0.007 and 0.029 for liquid and vapor CO 2 molar fractions, and 0.005 and 0.010 for liquid and vapor densities respectively. The Validation against experiment data on 10 binary systems and 316 state points shows that the predictions are accurate with average deviation of about 5% for CO 2 mole fraction and 3.5% for saturated density at pressure range to P P c . This automatic procedure can only be used for the prediction of the vapor-liquid equilibrium. The computed data can be obtained from http://sun.sjtu.edu.cn/msd .

A Fe 3 O 4 nanorods/graphitic C 3 N 4 composite was synthesized by a simple hydrothermal method. The structure and morphology of the composite were characterized by SEM, TEM, XRD, FT-IR and so on. The specific capacitance of the composite as an electrode material is 4.3 times as that of pure graphitic C 3 N 4 (g-C 3 N 4 ) at the discharge current density of 1 A/g, showing enhanced electrochemical performance. The improved capacitive performance could be ascribed to the synergetic effect between Fe 3 O 4 nanorods and g-C 3 N 4 . This work provides a new way to improve the electrochemical property of g-C 3 N 4 and shows that the Fe 3 O 4 nanorods/g-C 3 N 4 composite is a potential electrode material for high-performance supercapacitors.

External fields can decidedly alter the free energy landscape of soft materials and can be exploited as a powerful tool for the assembly of targeted nanostructures and colloidal materials. Here, we use computer simulations to demonstrate that nonequilibrium internal fields or forces -- forces that are generated by driven components within a system -- in the form of active particles can precisely modulate the dynamical free energy landscape of a model soft material, a colloidal gel. Embedding a small fraction of active particles within a gel can provide a unique pathway for the dynamically frustrated network to circumvent the kinetic barriers associated with reaching a lower free energy state through thermal fluctuations alone. Moreover, by carefully tuning the active particle properties (the propulsive swim force and persistence length) in comparison to those of the gel, the active particles may induce depletion-like forces between the constituent particles of the gel despite there being no geometric size asymmetry between the particles. These resulting forces can rapidly push the system toward disparate regions of phase space. Intriguingly, the state of the material can be altered by tuning macroscopic transport properties such as the solvent viscosity. Our findings highlight the potential wide-ranging structural and kinetic control facilitated by varying the dynamical properties of a remarkably small fraction of driven particles embedded in a host material., ACS Nano

In this paper, the CoZrTaB thin films are fabricated using sputtering on different substrates and characterized comprehensively. The CoZrTaB thin films have been fabricated in the single-layer and multi-layer structures with SiO2 as the insulator layer, of which the vibrating sample magnetometer results suggest that the saturation field and the coercivity change of the multi-layer structure can be minimized while the lamination structure can suppress the eddy current at high working frequency. Compared with the continuously sputtered 400 nm CoZrTaB thin film, the multi-layer thin film shows a hysteresis loop with a single domain and small coercivity. The surface roughness of each CoZrTaB thin film and two kinds of polyimide substrates is extracted by the atomic force microscope instrument. Besides, material characterization such as X-ray powder diffraction and Rutherford backscattering spectrometry have been conducted to acquire the information of phase and element ratio of the CoZrTaB thin film. Also, the different process conditions that could affect the magnetic properties are investigated and verified. A comparison is made with the previously reported results, sustaining the improvement of the CoZrTaB thin film on different substrates.

There are some problems in TiO2, such as poor visible light response, low surface area and high electro-hole combination efficiency, which limit its applications. A novel and efficient solvothermal method was developed using TiCl3 and glucose to prepare reduced TiO2/C (r-TiO2/C) nanocomposites. The results show that TiO2 in composite is anatase and reduced. Transmission electron microscope analysis indicates that the composites are composed of r-TiO2 and amorphous carbon in size of 8–14 nm. All samples have a good response in visible light and near infrared region. When 1.5 mmol glucose was used, the sample has the lowest band gap 1.30 eV according to Ultraviolet–visible spectroscopy, the degradation ratio of which for Rhodamine B reaches 92% after 70 min under visible light irradiation.

The CeVO 4 /graphitic C 3 N 4 composites were successfully synthesized by using a calcination method. X-ray diffraction patterns show that the diffraction peaks of both graphitic C 3 N 4 (g-C 3 N 4 ) and CeVO 4 coexist in composites. Transmission electron microscopy analysis shows that the CeVO 4 rods and particles are well distributed on g-C 3 N 4 layers and become larger after being calcined. The CeVO 4 /g-C 3 N 4 composites compared with single-phase g-C 3 N 4 and CeVO 4 exhibit much enhanced photocatalytic property in degrading methylene blue pollutant under visible light irradiation, which is mainly attributed to the formation of heterojunction between g-C 3 N 4 and CeVO 4 . The CeVO 4 /g-C 3 N 4 materials will have many potential applications in the photodegradation of other pollutants.

The graphitic C3N4 was modified by barbituric acid and denoted as BA-C3N4. Then, the BA-C3N4/Ag3VO4 composites with different contents of BA-C3N4 were prepared by codeposition-precipitation method. The specific surface areas of the composites were investigated via nitrogen absorption–desorption isotherms. The results show that after adding BA-C3N4 into Ag3VO4, the surface areas of the composites have been enlarged obviously. The photocatalytic performance of composites compared with that of BA-C3N4 and Ag3VO4 is effectively improved. The sample 30 wt% BA-C3N4/Ag3VO4 has the best photocatalytic activity, whose kinetic constant is seven times larger than that of both pure BA-C3N4 and Ag3VO4. The photocatalytic mechanism is proposed on the basis of active species trapping experiments in photocatalytic degradation process. It is suggested that the enhanced photocatalytic activity of composites is mainly attributed to the enlarged surface area and the heterojunction between BA-C3N4 and Ag3VO4, leading to an effective separation of the photoinduced electron–hole pairs.

Poor visible light response and high electron–hole recombination efficiency of TiO2 are main problems which limit its applications. A facile method was developed to prepare reduced TiO2/amorphous carbon composites with particle sizes of about 10–20 nm, which have good visible light absorption and low band gap energy (1.37 eV). The results show that the composite prepared using 1.5 mmol ascorbic acid at 180 °C has good crystallinity, strong visible light absorption and enhanced catalytic activity. The degradation efficiency of the samples for rhodamine B reaches 90% after 100 min under visible light irradiation.

Germanium on silicon has the potential to enable growth of high quality group IV semiconductors for the field of silicon photonics by being used as virtual buffers. In addition Ge layers can be used in the fabrication of passive components such as waveguides and resonators. A cost-effective technology for the heteroepitaxial growth of Ge on Si will be highly beneficial. In this work, a simplified chemical vapor deposition reactor was assembled in-house to deposit Ge films. Epitaxial Ge film growth on Si (100) substrates was accomplished without requiring ultra-high vacuum conditions or a high temperature substrate pre-deposition bake thereby minimizing the economic and thermal budget of the process. Films were deposited using digermane (Ge2H6) precursor in a single step at a process temperature of 350 °C and chamber pressures of 1–10 Torr. Films were achieved at high chamber background pressures (>10−6 Torr) by implementing a thorough ex situ substrate cleaning process and optimizing times for wafer loading, chamber pumping and initiation of film deposition. Transmission electron microscopy and X-ray diffraction were used to confirm the epitaxial growth and crystalline quality of the obtained films. Optical properties of the films were characterized using Raman spectroscopy, Photoluminescence and Infra-red spectroscopy.

A nanocomposite consisted of Ag nanoparticles and WS2 nanosheets was prepared by a two-step procedure, in which Ag sol was generated at first, then added into WS2 nanosheet dispersion to form the nanocomposite via self-assembly. The nanocomposites with different content of Ag nanoparticles were successfully prepared. The results show that Ag nanoparticles with the diameter of 10–20 nm are uniformly distributed on WS2 nanosheets and not oxidized. All nanocomposites are mesoporous. The specific surface area and the mesoporosity of WS2 are improved due to the existence of Ag nanoparticles. The specific capacitance of the nanocomposite increases with the increasing content of Ag nanoparticles. The 2000 cycles of charging and discharging were carried out on 20%AgNPs@WS2 nanocomposite, proving its good cycling performance. It has smaller transfer resistance and internal series resistance than WS2 nanosheets. This nanocomposite has potential application in supercapacitors.