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Metal-organic frameworks (MOFs) have been considered as a class of promising electrode materials for supercapacitors owing to their large surface area, rich porosity, and variable redox sites; however, direct application of pristine MOFs in energy storage has been largely hindered by their poor electrical conductivity and stability issues. In this work, we demonstrate a facile two-step approach to address the controlled growth of Ni-MOF arrays on the surface of NiCo 2 O 4 nanowires by modulating the formation reaction of MOFs. By taking advantage of the intriguing merits from the NiCo 2 O 4 core and Ni-MOF shell as well as their synergistic effects, the optimized NiCo 2 O 4 @Ni-MOF hybrid electrode exhibits boosted electrochemical performance, in terms of high specific capacity (208.8 mA h/g at 2 mA/cm 2 ) and good rate capability. In addition, the assembled flexible solid-state HSC device based on the optimized NiCo 2 O 4 @Ni-MOF and activated carbon as the cathode and anode achieves a maximum energy density of 32.6 W h/kg at a power density of 348.9 W/kg without sacrificing its outstanding cycling performance (nearly 100% retention over 6000 cycles at 8 mA/cm 2 ) and mechanical stability, outperforming most recently reported MOF-based HSC devices in an aqueous electrolyte. Our work demonstrates the possibility of exploiting novel MOF-based hybrid arrays as battery-type electrodes with enhanced electrochemical properties, which exhibits great potential in flexible energy storage devices.

The development of flexible energy storage devices for portable and wearable electronics has aroused increasing interest. In this work, three-dimensional hierarchical NiCo 2 O 4 @NiMn-LDH nanowire/nanosheet arrays have been successfully fabricated on carbon cloth through a facile hydrothermal and calcination synthetic method. Benefiting from the sophisticated hybrid nanoarchitectures with desirable structure and components, the optimized NiCo 2 O 4 @NiMn-LDH hybrid electrode is found to deliver a remarkable specific capacity of 278 mA h g -1 at 2 mA cm -2 and a good rate capability of 89.1% retention at 20 mA cm -2 . Detailed analysis of the reaction kinetics for the hybrid electrode clearly indicates the dominant diffusion-controlled contribution to the total capacity. In addition, a flexible solid-state hybrid supercapacitor is assembled by taking NiCo 2 O 4 @NiMn-LDH and activated carbon as the cathode and anode, respectively, which manifests a maximum energy density of 47 W h kg -1 at a power density of 357 W kg -1 as well as an excellent long-term cycling stability (95.6% retention after 5000 cycles over 8 mA cm -2 ). Our work demonstrates the great potential of this core/shell hybrid nanostructure as an advanced battery-type electrode for high-performance flexible energy storage devices.

To obtain high-performance hybrid supercapacitors (HSCs), a new class of battery-type electrode materials with hierarchical core/shell structure, high conductivity and rich porosity are needed. Herein, we propose a facile one-step sulfuration approach to achieve the fabrication of hierarchical NiCo 2 S 4 @NiCo 2 S 4 hybrid nanotube/nanosheet arrays (NTSAs) on carbon cloth, by taking hydrothermally grown Ni-Co precursor@Ni-Co precursor nanowire/nanosheet arrays (NWSAs) as the starting templates. The optimized electrode of NiCo 2 S 4 @NiCo 2 S 4 hybrid NTSAs demonstrates an enhanced areal capacity of 245 μA h cm -2 at 2 mA cm -2 with outstanding rate capability (73% from 2 to 20 mA cm -2 ) and cycling stability (86% at 10 mA cm -2 over 3000 cycles). In addition, flexible solid-state HSC devices are assembled by using NiCo 2 S 4 @NiCo 2 S 4 hybrid NTSAs and activated carbon as the positive and negative electrodes, respectively, which manifest a maximum volumetric energy density of 1.03 mW h cm -3 at a power density of 11.4 mW cm -3 , with excellent cycling stability. Our work indicates the feasibility of designing and fabricating core/shell structured metal sulfides through such a facile one-step sulfuration process and the great potential of these materials as advanced electrodes for high-performance HSC devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Though previous study indicated that the 580 nm-yellow-LED-light showed an stimulating effect on growth of chickens, the low luminous efficiency of the yellow LED light cannot reflect the advantage of energy saving. In present study, the cool white LED chips and yellow LED chips have been combined to fabricate the white × yellow mixed LED light, with an enhanced luminous efficiency. A total 300 newly hatched chickens were reared under various mixed LED light. The results indicated that the white × yellow mixed LED light had "double-edged sword" effects on bird's body weight, bone development, adipose deposition, and body temperature, depending on variations in ratios of yellow component. Low yellow ratio of mixed LED light (Low group) inhibited body weight, whereas medium and high yellow ratio of mixed LED light (Medium and High groups) promoted body weight, compared with white LED light (White group). A progressive change in yellow component gave rise to consistent changes in body weight over the entire experiment. Moreover, a positive relationship was observed between yellow component and feed conversion ratio. High group-treated birds had greater relative abdominal adipose weight than Medium group-treated birds (P = 0.048), whereas Medium group-treated birds had greater relative abdominal adipose weight than Low group-treated birds (P = 0.044). We found that mixed light improved body weight by enhancing skeletal development (R 2  = 0.5023, P = 0.0001) and adipose deposition (R 2  = 0.6012, P = 0.0001). Birds in the Medium, High and Yellow groups attained significantly higher surface temperatures compared with the White group (P = 0.010). The results suggest that the application of the mixed light with high level of yellow component can be used successfully to improve growth and productive performance in broilers., (Copyright © 2018. Published by Elsevier B.V.)

Bulk (Ga1-x Zn x )(N1-x O x ) as a photocatalyst has received increasing attention as a potential solution for the energy shortage challenge; however, its catalytic performance is highly limited by its bulk form. To improve the photochemical potential, the nanoscale form of this multiple-metal oxynitrides is desirable. In this work, a new type of (Ga1-x Zn x )(N1-x O x ) nanostructure is obtained. Its composition can tuned to the full range (0.18 < x < 0.95). The (Ga1-x Zn x )(N1-x O x ) nanostructure exhibits excellent photocatalytic activity for overall water splitting, and the highest quantum efficiency of (Ga1-x Zn x )(N1-x O x ) is as high as 17.3% under visible light irradiation. Using this new type of (Ga1-x Zn x )(N1-x O x ) nanostructure, the narrowing of the bandgap for (Ga1-x Zn x )(N1-x O x ) is not only due to an increase in the valence band maximum, but it is also related to a decrease in the conduction band minimum., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Bandgap engineering and shape control are important and advantageous for potential applications involving colloidal ZnO nanocrystals. Here we demonstrate the syntheses of high quality alloyed Cd(x)Zn(1-x)O nanocrystals with well-defined shapes, from faceted particles to tetrapods and ultrathin nanowires. By comparing the optical bandgaps of the pure ZnO, Cd(x)Zn(1-x)O and Mg(x)Zn(1-x)O nanocrystals with various dimensions, we conclude that bandgap engineering of colloidal ZnO nanocrystals via cadmium alloying effectively narrows the bandgaps. Our study may shed light on the design and syntheses of colloidal alloyed oxide nanocrystals with controlled band structures and shapes.