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Preparation, characterization and photocatalytic performances of materials based on CS2-modified titanate nanotubes

Abstract

CS2-modified titanate nanotubes (CS2/TiO2-NTs) are fabricated by reaction of CS2 and Ti-O−Na+ species on titanate nanotubes. Pb2+ ions are coated on the modified nanotubes by ion exchange (Pb/CS2/TiO2-NTs). The products are characterized by means of nitrogen adsorption-desorption isotherms at 77 K (BET method), transmission electron microscopy (TEM), X-ray photoelectron spectrometry (XPS), X-ray diffraction (XRD), atomic absorption spectrometry (AAS), and diffuse reflectance spectroscopy (DRS). The photocatalytic performances of the products are evaluated by monitoring their catalytic activities for degradation of methyl orange under UV light irradiation. The effects of calcination temperature and atmosphere on the photocatalytic performance are investigated. The results reveal that the photocatalytic activities of CS2/TiO2-NTs and Pb/CS2/TiO2-NTs are far higher than that of primary nanotubes, and the optimum calcination temperature is 500 °C under N2 atmosphere. It is also discovered that physically adsorbed Pb2+ ions affect the photocatalytic activity of Pb/CS2/TiO2-NTs obviously. The photocatalytic activity of washed Pb/CS2/TiO2-NTs is higher than that of the unwashed one under the same thermal treatment and reaction conditions.

Open access
Structure and performance optimization of phenol polyphosphazene grafted by 2,4-dinitroaniline containing small nonlinear optical molecules

Abstract

Electro-optic (EO) polymers, possessing high EO coefficient and low dielectric constant, are considered to be a new generation of nonlinear optical materials that have great application prospect in photo-communication, information storage, and data processing. The host-guest structure of EO polymers is the most typical one in this field. However, the phase separation during polarization between the host polymer and the guest nonlinear optical molecule (NLO) limits potential applications of the material. To solve the problem, a new synthetic method was designed in this paper. First, 2,4-dinitroaniline was grafted to phenol polyphosphazene by chemical method for polar improvement of the main chain. Then, another small NLO molecule was mixed into the polymer by physical method for further improvement of EO coefficient. The preparation process was studied and the structure of the product was characterized. The effects of different NLO mixing proportions and different polarizing temperatures on EO coefficient were investigated in details. Orientation stability of the sample was tested. Experimental results show that our products possess not only high EO coefficient but also good phase stability, which makes them good candidates for the application in information technology.

Open access
Hydrothermal synthesis and thermoelectric properties of PbS

high power factor (S 2 σ) and low thermal conductivity is an effective way to achieve high-performance thermoelectric materials. The rocksalt-structured lead-based chalcogenides, have been extensively studied as promising thermoelectric materials [ 1 , 6 - 9 ]. Especially lead telluride (PbTe), as one of the most frequently investigated materials in this system, remains the top-performing thermoelectric at midtemperature range (600 K to 900 K) [ 10 ]. However, Te is a scarce element in the crust of the earth (0.001 ppm by weight). Lead sulfide (PbS) is much less

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Enhanced gas-sensing performance of Au-modified ZnO nanoparticles synthesized using bamboo cellulose as a template

1 Introduction In past decades, with increasing usage of various dangerous gases in many areas, a lot of efforts have been made for development of highly sensitive gas sensors in order to deal with security problems existing in environment, industry and daily life. The crucial works are exploring novel materials with excellent gas-sensing performance to meet these demands. Oxide semiconductor is a suitable material for gas sensor fabrication due to its low cost, physical and chemical stability, easy synthesis, environment-friendliness, high sensitivity and

Open access
A New Method for Determining the Pullability of Composite Reinforcing Ceramic Fibres

composites: goveerning phenomena. Composites Part A: Applied Science and Manufacturing, 32/8. (2001) 981–996. https://doi.org/10.1016/S1359-835X(01)00015-X [9] Margueritat-Regenet C.: Elaboration et caractérisation de fils composites C/Al. Infiltration spontanée et continue par activation chimique du mouillage. Thèse de doctorat, Ecole nationale supérieure des mines, Paris, 2002. https://hal.archives-ouvertes.fr/tel-00005642/ [10] High-Performance structural fibers for advanced polymer matrix composites . National Research Council, The National Academies

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Method for Emissivity Estimation of Metals

=4468&-path%5B%5D=1466 [3] Liedquist L.: A radiometric method for measurement of emissivity of metallic surfaces . Non Nuclear Energies Workshop on Optical Property Measurement Techniques, Ispra, 1987. 277–280. [4] Wen C. D., Mudawar I.: Experimental investigation of emissivity of aluminum alloys and temperature determination using multispectral radiation thermometry (MRT) algorithms . Journal of Materials Engineering and Performance, 11/5. (2002) 551–562. https://doi.org/10.1361/105994902770343818 [5] Filep E., Kutasi N., Kenéz L.: A Sapientia

Open access
The Relationship between Materials Science and the Fourth Industrial Revolution

://www.congress.gov/111/plaws/publ203/PLAW-111publ203.pdf [4] Tisza M., Czinege I.: Comparative study of the application of steels and aluminium in lightweight production of automotive parts . International Journal of Lightweight Materials and Manufacture, 1/4. (2018) 229–238. https://doi.org/10.1016/j.ijlmm.2018.09.001 [5] Frazier W. E.: Metal additive manufacturing: A review . Journal of Materials Engineering and Performance, 23/6. (2014) 1917–1928. https://doi.org/10.1007/s11665-014-0958-z [6] Sandvik invests in metal powder plant . Heat processing, 2. (2018

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The Replacement of Resistance Welding with Laser Beam Welding

.: Impact of inter-sheet gaps on laser overlap welding performance for galvanised steel . Journal of Materials Processing Technology, 226. (2015) 157–168. https://doi.org/10.1016/j.jmatprotec.2015.07.020 [14] Bley H., Weyand L., Luft A.: An alternative approach for the cost-efficient laser welding of zinc-coated sheet metal. CIRP Annals, 56/1. (2007) 17–20. https://doi.org/10.1016/j.cirp.2007.05.006 [15] Pieters R. R. G. M., Bakels J. G., Hermans M. J. M., Den Ouden G.: Laser welding of zinc coated steels in an edge lap configuration . Journal of Laser

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Mechanical and Microstructural Features of Ceramic Hollow Spheres

-Aguilar C., Alfonso I.: Elastic Modulus Estimation for Copper Syntactic Foams Reinforced with Iron Hollow Spheres of Different Wall Thicknesses. Journal of Materials Engineering and Performance, 28/1. (2019) 100–106. doi.org/10.1007/s11665-018-3827-3 [9] Taherishargh M., Belova I. V., Murch G. E., Fiedler T.: The effect of particle shape on mechanical properties of perlite/metal syntactic foam. Journal of Alloys and Comppunds, 693. (2017) 55–60. doi.org/10.1016/j.jallcom.2016.09.168 [10] Fiedler T., Taherishargh M., Krstulovic-Opara L., Vesenjak M

Open access
Diethylenetriamine-assisted one-step hydrothermal synthesis of cotton-like CoS cluster for high-performance supercapacitor

Abstract

Cotton-like CoS cluster has been successfully synthesized via a simple one-step hydrothermal route assisted by diethylenetriamine (DETA) as a ligand and structure-directing agent. The structure and morphology of the product were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM) and N2 adsorption-desorption isotherm. The CoS sample which has a hexagonal phase without any impurities possesses a microscopic morphology made by cotton-like clusters. The as-fabricated CoS as a supercapacitor electrode presents desirable supercapacitive performance with a high specific capacitance (664 F∙g-1 at 0.5 A∙g-1), remarkable rate capability and excellent cycling stability (85.7 % specific capacitance retention after 1000 cycles), making it applicable as an electrode for high-performance supercapacitors.

Open access