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Metal-organic frameworks derived metal chalcogenides as a new class of active materials can abolish the existing challenges in supercapacitors with their large electroactive sites and enhanced electrochemical conductivities. With its adequate conductivity and electrochemical properties, tellurium based metal chalcogenide electrodes can deliver better electrochemical performances than other chalcogenides. Herein, CuCoTe honeycomb-like nanosheets are grown on nickel foam (CuCoTe HNSs/NF) and then CuCo layered double hydroxides are successively coated on them (CTC HLSs/NF). The CTC HLSs/NF electrode exhibits tremendous performance with its high specific capacity of 399 mAh g-1 at 7 A g-1 of current density and good capacity retention (81.3%) after 3000 cycles. Finally, CTC HLSs/NF electrode is utilized for the hybrid supercapacitor (HSC) assembly along with activated carbon coated nickel foam in an aqueous electrolyte. The fabricated HSC shows high energy density (214.7 Wh kg-1 ) and power density (40 kW kg-1 ). Moreover, the device retains 96.3% of its capacitance at the end of the 5000th cycle, showing its high stability. Owing to their unique morphology and superior electrochemical properties, the present method of fabrication and selected materials can address the issues faced by electrochemical capacitors.

The plasmonic coupling, the enhanced electromagnetic field occurring through a uniform and small separation between metallic particles, is required for better application to localized surface plasmon resonance. Graphene has been studied as a good spacer candidate because of its precise controllability at subnanoscale. Here, the enhancement of plasmonic coupling among metallic nanoparticles (NPs) uniformly spread out on both sides of a graphene spacer is experimentally and simulatively investigated. Additionally, the post-evaporated flat structure is rippled along one direction to reduce the separation between nanoparticles. As the amount of rippling increases, the enhancement factor (EF) of the plasmonic coupling increases almost linearly or quadratically depending on the size of nanoparticles. Such a highly rippled nanostructure is believed to not only increase the plasmonic coupling in either side of the spacer but lead to a higher density of “hot spots” through the spacer gap also. The observed EFs of a structure with the MLG spacer are consistent with the simulation results obtained from the classical electrodynamics. On the other hand, the SLG case appears to be inconsistent with such a classical approach, indicating that the plasmon tunneling through the thin barrier is prevalent in the case of the SLG spacer.

Pyrophosphoric lactone-modified polyester containing two phosphorous functional groups in one structural unit of base resin was synthesized to prepare a nontoxic, reactive flame-retardant coatings. Then, the pyrophosphoric lactone-modified polyester was cured at room temperature with isocyanate and isophorone diisocyanate (IPDI)–isocyanurate to get a two-component polyurethane flame-retardant coatings (TAPPU). Comparing the physical properties of the films of TAPPU with the film of nonflame-retardant coatings, no deterioration of physical properties was observed with the incorporation of a flame-retarding component into the resin. Three kinds of flame retarding tests were conducted, including the 45° Meckel burner method, limiting oxygen index method (LOI method), and oxygen combustion method with Cone calorimeter. It was observed that the char lengths were 3.1∼4.5 cm and LOI values were 27∼30%. These results indicate that the prepared coatings are good flame-retardant ones. It was also found that the flame retardancy of those coatings was increased with the contents of phosphorous. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2316–2327, 2001

DOI: 10.1002/aelm.201500331 nanogenerator (TENG). The output voltage and current from the TES increase up to peak-to-peak values of 450 V and 0.14 mA cm −2 , respectively. This is a ten-fold power enhancement compared to those of a control group (fl at PDMS fi lm) under the same mechanical force. The electrical output performance of the TES was measured under wide ranges of mechanical stress. Various TESs were also fabricated using different grain sizes of cube sugar for various pore sizes. The output voltage and current density increase with a decrease in the pore size of the TES. Compression measurements were also conducted to evaluate the resistance to deformation by external force. These experiments showed that the elastic modulus decreases by more than 30% in a sponge typePDMS fi lm. Thus, the TES become more fl exible, and simultaneously the contact area by the micro structure increases when external mechanical force is applied. In addition, we report a very stable and high output performance of the TESs under a wide range of humidity conditions. We also show that a large number of light-emitting diodes (LEDs) can be powered by electrical output power generated by the TES under the application of mechanical strain, even in very humid conditions. Schematics for the fabrication procedure of the triboelectric sponge are shown in Figure 1 a. The fabricated TES was manufactured with 3D soft lithography with three sizes of sugar particles (see the Experimental Section for details of the fabrication steps). The sugar particles used here were commercially available in a nearby market. The cubic-shaped sugar particles used as casting templates are shown in Figure 1 c. It is seen that all sugar particles have a uniform cubic-shape. The three types of sugar particles used, large, medium, and small, have dimensions of 1500, 500, and 300 μm, respectively. As a result of casting and curing, highly porous and elastic PDMS thin fi lms were formed with the free-standing structure shown in Figure 1 a. The surface morphologies of TES fabricated with different diameters of the sugar particles are shown in Figure 1 c. This fi gure clearly shows that the PDMS sponge was very uniformly formed. Moreover, its microstructures were confi rmed by the scanning electron microscope image in Figure 1 d. To fabricate an electrical generator using the TES, thermally evaporated Au (100 nm) onto an acrylic substrate were located at one side of the TES. Then, four springs were fi xed between two electrodes for mechanical support and separation. A conceptually simplifi ed device scheme of the fabricated TES embedded generator is presented in Figure 1 b. Additionally, actual digital images of the TES are shown in Figure S1 (Supporting Information). For a fair comparison of Due to the global energy crisis and environmental problems such as global warming, energy harvesting technology has emerged as an alternative to current energy technology. Sustainable and eco-friendly energy harvesting from surrounding environment, such as solar energy, wind, tide, and mechanical vibration, has attracted a great deal of attention as researchers attempt to solve the worldwide energy crisis. [ 1 ] Thus far, diverse types of energy sources have been converted into electricity based on various physical principles, such as piezoelectric, [ 2–6 ]