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Copper microcubes about 500 nm were electrodeposited on ITO glasses. Silver nanoparticles, netty consist of short nanorods or nanowires, nanosheets with thickness about 40 nm, were successfully obtained by immersing ITOs with different concentration of AgNO 3 solution. XRD, SEM and TEM were applied to characterize the products. Silver ions were initially reduced on the surface of copper, and then gradually decomposed the copper. Cuprous oxide intermediate was found to participate in the redox reaction. Both agglomerates on the cubes and escaped reductant nanoparticles act as the positions for anisotropic growth. Based on the experimental results, the roles of three kinds of cubes are discussed in preparing the nanosheets before proposing the possible growth process. Oriented attachment influenced and controlled the final shapes, such as layered nanonets, nanoplates and nanosheets. Big nanoparticles were inclined to link as nanowires, netty and even 2D porous structure consisted of ‘nanosnakes’, small reductant nanoparticles with silver around absorbed on the edge of silver nanoplate and further accelerated the extension of nanoplate until worked out, holes on the nanoplate confirmed that the adsorbed matters could be reductant nanoparticles. Reductant nanoparticles can also be exhausted before silver nanoparticles and nanoflakes absorbed on the growth positions. [ABSTRACT FROM AUTHOR]

Hybrid nanostructures of N-doped mesoporous carbon@NiCo 2 O 4 with controllable compositions are prepared by a facile hydrothermal method. Various morphologies of N-doped mesoporous carbon@NiCo 2 O 4 are successfully synthesized including sea urchins-like structure of free NiCo 2 O 4 , litchi chinensis-like structure of NC-100@ NiCo 2 O 4 and waxberry-like structure of NC-200@ NiCo 2 O 4 . All samples exhibit excellent rate capability and cycle stability. The incorporation of N-doped mesoporous carbon causes a dominant capacitance increase. Free NiCo 2 O 4 only possesses a specific capacitance of 1038 F g −1 at 1 A g −1 , while NC-200@ NiCo 2 O 4 renders a much higher specific capacitance of 1624 F g −1 , which shows a distinct improvement of 56.4%. Moreover, NC-200@ NiCo 2 O 4 still performs a high specific capacitance of 1360 F g -1 even at a high current density of 10 A g −1 . Besides, the final capacitance can still maintain 94.3% of the initial capacitance even after 10,000 cycles. [ABSTRACT FROM AUTHOR]

Strain engineering is a promising method for tuning the electronic properties of two-dimensional (2D) materials, which are capable of sustaining enormous strain thanks to their atomic thinness. However, applying a large and homogeneous strain on these 2D materials, including the typical semiconductor MoS 2 , remains cumbersome. Here we report a facile strategy for the fabrication of highly strained MoS 2 via chalcogenide substitution reaction (CSR) of MoTe 2 with lattice inheritance. The MoS 2 resulting from the sulfurized MoTe 2 sustains ultra large in-plane strain (approaching its strength limit ~10%) with great homogeneity. Furthermore, the strain can be deterministically and continuously tuned to ~1.5% by simply varying the processing temperature. Thanks to the fine control of our CSR process, we demonstrate a heterostructure of strained MoS 2 /MoTe 2 with abrupt interface. Finally, we verify that such a large strain potentially allows the modulation of MoS 2 bandgap over an ultra-broad range (~1 eV). Our controllable CSR strategy paves the way for the fabrication of highly strained 2D materials for applications in devices., Competing Interests: Conflict of interest The authors declare that they have no conflict of interest., (Copyright © 2021 Science China Press. Published by Elsevier B.V. All rights reserved.)