A new self-powered broadband photodetector was fabricated by coating an n-silicon nanowire (n-Si NW) array with a layer of p-cupric oxide (CuO) nanoflakes through a new simple solution synthesis method. The p-n heterojunction shows excellent rectification characteristics in the dark and distinctive photovoltaic behavior under broadband light illumination. The photoresponse of the detector at zero bias voltage shows that this self-powered photodetector is highly sensitive to visible and near-infrared light illuminations, with excellent stability and reproducibility. Ultrafast response rise and recovery times of 60 and 80 μs, respectively, are shown by the CuO based nanophotodetector. In addition, the broadband photodetector can also provide a rapid binary response, with current changing from positive to negative upon illumination under a small bias. The binary response arises from the photovoltaic behavior and the low turn-on voltage of the CuO/Si NW device. These properties make the CuO/Si NW broadband photodetector suitable for applications that require high response speeds and self-sufficient functionality.

Rechargeable aluminum-ion batteries are considered promising candidates for the new generation of energy storage systems because of their high capacity, low cost, and high security. The most urgent challenge to be addressed for the practical application of aluminum-ion batteries is exploring cathode materials with simple fabrication processes and preeminent electrochemical performance. Herein, a flexible free-standing MoS 2 /carbon nanofibers composite has been successfully synthesized by electrospinning and annealing treatment and investigated as a cathode material for rechargeable aluminum-ion batteries, delivering an initial discharge capacity of 293.2 mA h g −1 at a current density of 100 mA g −1 and maintaining 126.6 mA h g −1 after 200 cycles. The novel free-standing MoS 2 /carbon nanofibers composite can provide new ideas for the use of transition-metal sulfides as cathode materials for aluminum storage and facilitate the commercial adoption of aluminum-ion batteries.

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Mg-3wt%Al anodes with Sn, Ga and In were prepared by melting and heat-treatment in electric resistance furnace. The electrochemical discharge behavior of these anodes in 3.5wt% NaCl solutions was studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The microstructures and the corroded surfaces of the anodes were investigated by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). Finally, Mg-air batteries based on Mg-3Al-1Sn (AS31), Mg-3Al-1Ga (AG31), Mg-3Al-1In (AI31) alloys were prepared and battery properties were studied by constant current discharge test. Mg-3Al (A3) and Mg-3Al-1Zn (AZ31) were also prepared to be used for contrast test. The results show AI31 behaves good comprehensive properties, the battery based on AI31 anode possesses the highest capacity density (1382 mAhg−1) and power density (18.5 mWcm−2). Compared with A3 and AZ31, AS31 and AG31 show higher corrosion resistance. In addition, The paper also researches on the modification mechanism of Ga, In and Sn on Mg-3Al.