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As a lithium-ion battery cathode material with high theoretical capacity, the application of V2O5 is limited by its unstable structure and low intrinsic conductivity. In this paper, we report a Fe doped V2O5 nanowire with a layered structure of 200–300 nm diameter prepared by electrostatic spinning technique. The 3Fe-V2O5 electrode exhibited a superb capacity of 436.9 mAh g−1 in the first cycle when tested in the voltage range of 2.0–4.0 V at current density of 100 mA g–1, far exceeding its theoretical capacity (294 mAh g−1), and the high capacity of 312 mAh g−1 was still maintained after 50 cycles. The superb performance is mainly attributed to its unique layered nanowire structure and the enhanced electrical conductivity as well as optimized structure brought by Fe-doping. This work made the homogeneous doping and nanosizing of the material easily achieved through electrostatic spinning technology, leading to an increase in the initial capacity of the V2O5 cathode material and the cycling stability compared to the pure V2O5, which is an extremely meaningful exploration.

Broadband response photodetectors have received great research interest in optical sensing field. Usually, materials with positive photoconductivity (PPC) are general and the lack of negative photoconductivity (NPC) materials limits the application of photoelectric effect, especially in the broadband photodetecting field. Therefore, the finding of NPC materials is very important. Integrating PPC and NPC response into a single device is extremely meaningful to the development of broadband photodetector. In this work, we fabricated CsPbBr3 nanocrystals (NCs)-multilayered graphene heterojunction, which achieved persistent NPC response to ultra violet (300–390 nm) and PPC response to visible light (420–510 nm). The persistent NPC relies on the desorption of H2O vapor, and varies its intensity with the power intensity of laser. The PPC relies on the holes transmission from NCs to graphene. The recombination of NPC and PPC effect provides background knowledge for the development of broadband photodetector.

In this paper, fibrous-shaped of V6O13 were successfully synthesized via V2O5 and ethanol as reactants through the method of magnetic stirring in the oil bath, Compared to the prepared sample without mechanical force-driven, the sample prepared by this method has a fibrous morphology with good dispersion. It can be seen that as the speed increases, the width of the fibers decreases, the fiber length increases after SEM tests. After the electrochemical tests, it can be seen that the attrition rate of capacity will be successfully inhibited in the process of charging and discharging when the fibrous-shaped V6O13 as a lithium ion batteries cathode materials. When the stirring rate was 0 rpm and possessed a reversible capacity of 72 mAh/g after 50 deep cycles. By contrast, the stirring rate was 1200 rpm and possessed a reversible capacity of 102 mAh/g after 50 deep cycles. It increased 41.6%.

Mn-doped VO2(B) was synthesized via a hydrothermal reaction from manganese sulfate (MnSO4) and Vanadyl oxalate (VOC2O45H2O). The effects of the content of Mn on the electrochemical performance of material were studied by means of galvanostatic charge-discharge, cyclic voltammetry and electrochemical impedance spectroscopy (EIS). Compared with pure material VO2(B), the MnxVO2(B) which was doped with little Mn(x=0.01,0.02,0.05) had higher specific capacity and more preferable cycle performance. When galvanostatic charged-discharged with 0. 1 C in 1.5-4.0 V. the initial discharge specific capacity of sample Mn1, Mn2 and Mn3 were 204 mAh g−1, 242 mAh g−1 and 249 mAh g−1 respectively larger than pure VO2 sample (181mAh g−1). In particular, the sample of Mn1 exhibited best electrochemical performance. The initial discharge capacity maintained 164 mAh g−1 after 50 cycles. The retention rate of capacity was 80%.

The precursors of CIS and CIGS thin films were prepared by one-step electrodeposition in alcohol solution and then annealed in Ar atmosphere at 550°C for 30min. The influences of deposition potentials and salt concentrations on the morphology and composition of the thin films were studied in details. The films were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), and energy-dispersive X-ray spectroscopy(EDS). The results show that annealed films have pure CIS or CIGS phases with good crystallization and the morphology of the films are very uniform and dense. The high quality precursor films were obtained using optimized deposition parameters. Moreover the electrodeposition mechanism of CIS thin films was briefly discussed.