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In this paper, we report a new kind of beam, named “spoon-like” beams, generated with the exponential phase. The intensity distributions and transverse energy flow of the spoon-like beam at the focal plane are analyzed theoretically and experimentally. The results demonstrate that the size of the spoon-like beam becomes enlarged with the increasing power exponent n, and the length of the spoon-like intensity trajectory becomes shorter with the increasing parameter p. Furthermore, there is an intensity gradient along the spoon-like trajectory of the beam, which introduces the intensity-gradient force exerted onto microparticles. The experiment on optical tweezers demonstrates that the focused beams can create spoon-like traps for the two-dimensional manipulation of particles.

Faraday pseudocapacitors take both advantages of secondary battery with high energy density and supercapacitors with high power density, and electrode material is the key to determine the performance of Faraday pseudocapacitors. Transition metal oxides and nitrides, as the two main kinds of pseudocapacitor electrode materials, can enhance energy density while maintaining high power capability. Recent advances in designing nanostructured architectures and preparing composites with high specific surface areas based on transition metal oxides and nitrides, including ruthenium oxides, nickel oxides, manganese oxides, vanadium oxides, cobalt oxides, iridium oxides, titanium nitrides, vanadium nitrides, molybdenum nitrides and niobium nitrides, are addressed, which would provide important significances for deep researches on pseudocapacitor electrode materials.

WSe2 films were prepared on inexpensive graphite substrate through direct-current magnetron sputtering and rapid selenization for catalytic application in the hydrogen evolution reaction (HER). The effects of the temperature and time in selenization process on the HER activity were studied in details. Scanning electron microscopy and Raman spectroscopy indicates that the graphite surface is covered by WSe2 nanosheets. The HER activity of WSe2 samples prepared at different conditions has been evaluated via linear sweep voltammetry. Through adjusting selenization parameters, the WSe2 nanofilms consists of the proper nanosheets has been prepared with the optimal HER activity. It’s important to control the number, the size and crystallinity of WSe2 nanosheets which take responsibility for the HER activity. WSe2 electrodes prepared at 500 °C for 10 min exhibit high stability in acidic solution and get the optimal activity with an over potential around −179 mV vs reversible hydrogen electrode (RHE) at the current density of 10 mA cm−2.

Inexpensive graphite substrate is applied to grow WSe2 nanofilms for catalytic application in the hydrogen evolution reaction. W nanofilms with a thickness of about 10 nm were deposited onto the graphite substrate by direct-current magnetron sputtering. The graphite with 10 nm W nanofilms was rapidly selenized at 600 °C in horizontal tube furnace to form WSe2 nanofilms. Scanning electron microscopy, Raman spectroscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy indicated that graphite surface was covered by nano-sized vertically aligned WSe2 platelets. The effects of the N2 pressure in the selenization process on the HER performance have been studied in details. Turning of the selenization parameters can optimize the HER performance of the WSe2 nanofilms, which has been evaluated via linear sweep voltammetry and Tafel slope. WSe2 nanofilms prepared at the highest N2 pressure of 0.08 MPa behave optimal performance. The current density reaches 10 mA cm−2 at an over potential around −189 mV vs reversible hydrogen electrode and corresponding Tafel slopes is ∼72 mV dec−1. WSe2 nanofilms electrodes exhibit high stability in acidic solution which shows no degradation after 10000 continuous cycles. Thus, WSe2 nanofilms exhibit superior electrocatalytic performance which is much better than those recently reported grown on carbon paper substrate and W foil.

Reduced graphene oxide (RGO) sheets with varied contents and types of oxygenated groups were synthesized by Hummers treatment of natural graphite powders followed by different nontoxic and mild reduction methods, which include thermal and chemical reduction with ethylene glycol, KOH and Fe powder. The changes in microstructure and surface chemistry of RGOs were extensively characterized by SEM, TEM, AFM, XRD, XPS and Raman spectrum. The results show that significant exfoliation occurs during oxidation and is retained in reduction processes, along with the formation of curled wavy morphology. Compared with large d spacing (0.852 nm) of graphene oxide (GO), the (002) plane distance decreases to 0.358-0.384 nm of RGOs, indicating efficient tuning of surface functionalities through mild reduction methods. The I D/I G ratio of RGOs is about 1.0-1.15, indicating that reconstructed sp2 domains have smaller sizes and larger quantity. The content of sp2 bonded C in GO (36.93%, molar fraction) increases to 45.48%-72.92% (molar fraction) in RGOs, along with a drastic decrease in hydroxyl and epoxy and minor changes in carbonyl and carboxyl. Thermal reduction or chemical reduction produces RGOs with residual functionalities, which may render different chemical activity and is desirable in various applications.

A porous ternary nanocomposite based on graphene, RuO2 and TiO2 has been prepared via a facile in-situ co-assembly without any surfactants. A unique morphology of highly-curled graphene sheets loaded with sporadic spots or coatings comprised of mixed RuO2 and TiO2 nanodots was achieved for the first time. This uniform decoration indicates strong interaction between graphene and the as-grown nanoparticles favoring the full separation of graphene sheets. The formation mechanism of such a porous but tightly bonded hetero-nanostructure benefiting from linking effect of TiO2 is proposed. Electrochemical tests showed a characteristic capacitive behavior and the specific capacitance values of 216.7–396.5 F/g depending on the ratios of Ru/Ti, which has potential for energy storage.

Using graphene oxide and hydrous ruthenium chloride as starting materials, RuO 2 /graphene composites were prepared via a hydrothermal reaction under different precipitation conditions by using ammonium carbonate, urea, and sodium hydrate as precipitants. The morphology and structure of the RuO 2 /graphene composites were characterized by SEM, TEM, XRD. Cyclic voltammetry, galvanostatic charge–discharge, and impedance measurements were carried out to test the electrochemical performance. The results revealed that the veil-like RuO 2 /graphene composite prepared by sodium hydrate precipitation showed better capacitance performance than a particle-like composite prepared by ammonium carbonate and urea precipitation. A disproportionation reaction from Ru 3+ to Ru and RuO 2 took place in the RuO 2 /graphene composite when using CO(NH 2 ) 2 as the precipitant. The RuO 2 /graphene composite using sodium hydrate as the precipitant exhibited the optimum electrochemical performance with superior specific capacitance of 528.5 F g −1 at 0.1 A g −1 , minimum resistance (0.4 Ω), and excellent rate performance and cycling stability, suggesting the synergetic effects of the Ru(OH) δ Cl 3−δ precursors and graphene oxide during the hydrothermal process.

We report here characterization of the interfacial microstructure and properties of titanium dioxide (TiO2) nanotube array films fabricated by anodization. Field effect scanning electron microscopy (FESEM), X-ray diffraction (XRD), nanoindentation, atomic force microscopy (AFM), selected area electron diffraction (SAED), and high-resolution transmission electron microscopy (HRTEM) were used to characterize the interface of the film. With increasing annealing temperature from 200 °C to 800 °C, the interfacial fusion between the film and the Ti substrate increased. The phase transformation of the TiO2 nanotube film from amorphous to anatase to rutile took place gradually; as the phase transformation progressed, the force needed to break the film increased. The growth of TiO2 nanotube arrays occurs in four stages: barrier layer formation, penetrating micropore formation, regular nanotube formation, and nanofiber formation. The TiO2 nanotubes grow from the Schottky interface layer rather than from the Ti substrate. The Schottky interface layer's thickness of 35–45 nm was identified as half the diameter of the corresponding nanotube, which shows good agreement to the Schottky interface layer growth model. The TiO2 nanotube film was amorphous and the Ti substrate was highly crystallized with many dislocation walls.

Nanocomposites of reduced graphene oxide (RGO) sheets decorated with amorphous ruthenium oxide nanoparticles are fabricated through a one-pot hydrothermal process without additional dispersants. During the hydrothermal reduction, unilamellar graphene sheets with curved and veil-like morphology are formed and multilamellar graphene sheets are further separated by amorphous RuO2·xH2O with a particle size of 3–8 nm. The nanocomposites exhibit evident pseudo capacitance behavior and the comprehensive electrochemical performance is improved markedly compared with that of the single components. When the precursor ratio of graphene oxide (GO) to RuCl3·xH2O is 2:10, the graphene–RuO2 (GR) nanocomposite electrode achieves the highest specific capacitance of 542.5 F g−1 and the minimum ESR value of 1.21 Ω at 0.1 A g−1, retaining 94% after 1000 cycles at 1 A g−1. Thus graphene sheets/ruthenium oxide nanocomposites bode well for a promising candidate in supercapacitor technology.

Flake silver powder has attracted tremendous interesting due to its specially electrical and optical properties. Chemical reduction method with the advantages of reaction conditions easily controlled and mass production is widely used to prepare flake silver particles. In order to more easily prepare flake silver particles, the generation mechanism of flake silver particles is studied by analyzing the impacts of reaction conditions, such as pH value, kinds of silver seeds, kind of surfactant and concentration of raw material. The results show that flake silver particles can be prepared through controlling reaction conditions. Some problems existing in the preparation of flake silver particles are put forward, and future research directions are also proposed.

The performances of three kinds of water-based pigment inks were compared and studied, which include self-made ink, original printing ink and compatible ink. Art paper, matte paper and white card paper were used as the substrates. Testing the contact angle of ink droplets, the spreading, wetting, and drying rate of inks were investigated. The color density and CIE L*a*b* values of the printed samples were measured, to evaluate the hue error and color gamut. The water resistance was studied with corresponding experiments. The result indicates: self-made water-based pigment ink has the smallest contact angle on coated paper, showing a faster drying rate. Its color gamut is similar to the original printing ink on art paper, and the hue error is low. Through the water resistance test, the color density measured on art paper and matte paper had no changes, without color dissolving and color fading, showing good water resistance applicability.

Environment protection has aroused big concern in industrial development nowadays, and the printing industry has always been known as a big paper consumer and environmental pollution "contributor". In 1980s, Europe and the United States pioneered the concept of environment-friendly printing. China has also issued “Regulations for Environmental Labeling Products—Ink” since the 2008, which contains similar provisions of limited demand with those regulations of USA, EU, Japan, New Zealand and other countries. Environment-friendly ink is the key to achieve environment-friendly printing, and fine chemicals as an indispensable component is the sticking point to control. This paper describes the relevant laws of environment-friendly ink, types of environment-friendly colorant and the actual application, such as in inkjet and flexographic printing field.

The RFID antenna is mainly fabricated by metal coil winding, copper or aluminum etching, plating, printing and so on. In this paper, the comparison of above methods is conducted and the progress of the printing method and water-based conductive ink are emphasized. Water-based conductive inks are environmental-friendly, economic, high applicability, and are widely used in screen printing, gravure, flexible printing, inkjet printing, etc. Although starts late and the technology is not very mature, the RFID antenna prepared by printing method has many advantages, such as low cost, high precision, easy operation, variety of substrates, etc. Thus the printing has great potential applications on the fabrication of RFID antenna. Furthermore, water-based conductive inks used in ink-jet printing RFID antenna will be the first choice of printed RFID antenna.

The performance of the dispersion of cobalt blue in organic solvent is studied. The influence of dispersant (type & dosage), pH value, and other dispersion parameters on the stability of cobalt blue dispersion system is tested which shows good stability and excellent dispersion performance with diethylamide glycol ether the solvent, complex formulation (M (KH550): M (KH560): M (A-842) = 1:1:2) the dispersant and 7 the pH value. The characteristics of dispersion system are evaluated through sedimentation experiment and measurement of article size distribution. The most steady dispersion system is formed through high speed shearing force and the size of cobalt blue in this system is about 300nm.

In order to compare different concentration modes' influence on the nano-silver particle size and morphology,we use three methods to refine nano-silver solution prepared in the lab as:1 centrifugal the solution directly,2 deposit the solution with acetone,3 centrifugal the solution with acetone added.Then test the solution processed with particle size distribution,UV-vis and SEM.The result shows that:the particle sizes of the nano-silver solutions enriched with the three methods are 162.5nm,163.5nm,164nm;the peak of the UV-vis absorption curve are 425nm, 426.5nm,427nm,we can see that different methods of enrichment have less influence on the nano-silver particles' size and morphology. Also the same conclusion can be drawn from SEM test.

Antenna of RFID tag is used to spread frequency signals and build wireless connection between the tag and reader. High cost, low production speed and environment pollution exist in the traditional methods of manufacturing antenna. In order to overcome the disadvantages above, the method of printing antenna with conductive ink is being widely researched. So, conductive ink gets more and more attention. In order to study the performances of conductive ink better, conduction mechanism of conductive ink are mainly discussed. The requirements of conductive ink to print antenna are described. The present status of conductive ink in printing antenna is introduced, and research directions in future are also predicted.

In order to anticipate the color of dye ink more accurately, WENZHOU Mernuo Red-10 as an example, who was dissolved in different polarity solvent by magnetic stirring and ultrasonic agitation, the influence for properties of solvent on color of dye was researched with the coating method through contrasting sample papers. The influence for pH values of the solution and adding water to Red-10 solution on color of dye were also researched. It's shown that with the increased polarity of the solution,the absorption wavelength of Red-10 reduced gradually,light shade effect was caused. For the same solvent,with the pH values of the solvent increased,the absorption wavelength of Red-10 reduced gradually,light shade effect was caused.And all the factors affect the L,a,b values of the Red-10 dye's samples.

This study aims to analyse how inks of different colorant present unlike printing quality on selected substrates in inkjet printing. Applying Epson piezoelectric inkjet printer, experiments of printing pigment-based ink and dye-based ink on various substrates (coated art paper, porous photo paper, swellable photo paper, PP synthetic paper, xuan paper and PET-based coated film) were carried out respectively. Using digital microscope, the spreading, penetrating and distributing of ink drops were observed. Water fastness and light fastness were evaluated through aging test and water-immersing test, by measuring the decreasing of optical solid density. Taking the formula of inks and the composition of coating layers into consideration, contrast and analysis of print quality with different black inks on substrates of diverse support body were studied. The result demonstrates: Both dye-base and pigment-base inks present ideal optical density in special-purpose photo paper (swellable or porous type), exhibit distinct writing picture edge, and excellent water fastness and light fastness. While, coated art paper, PP synthetic paper, xuan paper and PET-based coated film, which shows relatively rough surface or weak ink absorbancy, are more suitable to use pigment-based ink.

In order to study the dispersion and performance of tartrazine aluminum lake, 7 kinds of water-based resins are used to form disperse system. These systems are enviroment friendly (low VOC) and use edible yellow lake as colorant. If proper adjustment is added, these disperse systems can be made into ink and paint. The application field should be printing or coating on all the food or drug packages, toys and decorate materials, which will improve social safe level. Colorant, resin, wetting agent, co-solvent, emulsifier, and deionized water are mixed at certain ratio and pre-dispersed for 15min, then dispersed in GJ-2S high speed sanding mill for 3h. Size distribution, PDI, color characteristics (reflectance spectroscopy and color density), glossiness, abrasion performance, and stability are studied. Results demonstrate particle size of disperse system is 338.1~595.3nm (PDI

Water-based polyurethane forms continuous and dense film after fully drying. Ink is lowly absorbed by PU film, affecting drying rate and color reproduction. In order to improve the absorption of ink on PU film, PU/nano alumina compound was prepared by adding nano alumina in PU and stirring at high speed. PU ink absorption coating was got by being coated on the substrate. The influences of different content of nano alumina to transmittance of coating and solid density of color blocks were researched. The influences of soft and hard segment of PU to image resolution and water resistance were also researched. It can be seen that transmittance reduces when content of nano alumina increases. Droplets spread less when using PU of hard segment and image resolution and solid density are also higher. At the same time, water resistance of solid blocks is much better when printed on PU of hard segment.

In order to evaluate the practical application effect of the self-made water-based coated paper inkjet ink and to study the influence factors, their printing performance and the influence of the printed material for printing performance is studied. The drying time of coated paper ink and ordinary water-based inkjet ink are measured and compared. Drying process of ink droplet is recorded by video contact angle tester. It is found that the drying rate of the coated paper ink is higher than the ordinary ink and the diffusion of the ordinary ink is severe. The coated paper ink and ordinary ink are printed, and it is found that the former can get better image detail and color reproduction for the picture of human’s face and inanimate object. The coated paper ink can also obtain a better reproduction of tone levels. Coated paper inkjet ink is printed on different coated papers, and the color densities are measured through red, green and blue color filter. The color strength and hue error are obtained to evaluate the color characteristics on different papers. It is concluded that the coated paper inkjet ink can obtain better color on the Henglian gloss coated paper, Sunbrite gloss coated paper and SPCO matt coated paper.

In order to acquire conductive film with high transparency, conductive polymer PEDT: PSS was mixed with some polar dopants and some surfactants. The coating fluid was acquired and coated on the PET film with different coating rods, and conductive film was gotten after drying at some temperature. The conductive mechanism of polymer after doping was introduced. Furthermore, the influenced factors of conductivity were discussed, including different dopants and surfactants as well as dried temperature. It was concluded that DMSO and EG were the best dopants, that surfactants including fluoride or silicon were suited for high conductivity. The sheet resistance of conductive film can be less than 300 Ω/□ when dried at 130 oC, at the same time the transparency at 550 nm is more than 83%. After measuring with AFM, the surface of film was sharp and the surface roughness is 7nm.