Carbon nanotubes (CNTs) have attracted remarkable attention as reinforcement for composites owing to their outstanding properties1-3. CNT/Cu nanocomposites were fabricated by mixing the nano-sized Cu powders with multi-wall carbon nanotubes and followed by the spark plasma sintering process. The CNT/Cu nanocomposite fabricated from nano-sized Cu powders shows more homogeneous distribution of CNTs in matrix compared to that fabricated from macro-sized Cu powders. The hardness of CNT/Cu nanocomposite fabricated from nano-sized Cu powders increases with increasing the volume fraction of CNTs, while the hardness of that fabricated from macro-sized Cu powders decreases with the addition of CNTs.

Herein, we successfully synthesize Mn2O3 multishelled hollow nanospheres through simply oxidizing Mn-based metal-organic framework microspheres. The number of the shells reaches 4. Many cavities and nanograins are hidden underneath the shell. The multishelled hollow structure brings about a wide hierarchical mesopore size range, large pore volume (0.26 cm3 g−1) and high specific surface area (117.6 m2 g−1). The superior zinc-ion storage performance may be achieved. The reversible capacity reaches 453 mAh g−1 at current density of 0.1 A g−1. After 500 cycles at 1 A g−1, the discharge capacity of 152.8 mAh g−1 is still delivered. The discharge capacity at 1.5 A g−1 stabilizes at 107 mAh g−1. The zinc storage process is further studied through kinetics analyses. It is found that in the zinc storage process, ion diffusion process and capacitive process occur simultaneously, and the capacitive process is dominant. The excellent electrochemical performance is mainly attributed to the multishelled hollow nanosphere structure of Mn2O3. This structure promotes contact of electrode materials/electrolyte, offers more active sites, facilitates infiltration of electrolyte, buffer volume change of Mn2O3, improving electrochemical activity, reaction kinetics and cycling performance of Mn2O3. Overall, Mn2O3 multishelled hollow nanosphere is an excellent cathode material for aqueous zinc-ion batteries.

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The sunshade method for the measurement of the ideality factor and resistances of solar cells is commonly used in silicon solar cells. However, the method is rarely employed for thin-film solar cells. In this paper, the sunshade method is applied to CIGS solar cells, and it is shown that the three major assumptions of the method remain valid for CIGS solar cells. The extracted parameters are compared to those calculated using other common methods, and the ideality factors and R s values are quickly determined and found to be nearly the same as those extracted through illuminated I-V fitting and dark I-V fitting.