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The photogalvanic effect (PGE) generated under linearly polarized light irradiation has remarkable applications in 2D nanodevices. The PGE of 2D WS2/Mo2CF2van der Waals (vdW) heterostructure can generate photocurrent and high sensitivity to polarized light. However, the PGE has less photogenerated current. On this basis, the photocurrent transport mechanism of PGE under low bias voltage is investigated. The results show that the photocurrent of the photon energy has cos2θ, sin2θand sin2θdependence on the polarization angle θunder the considered external bias voltage. Under a bias voltage of 1.0 V, the maximum photocurrent of 3.7 eV photon energy in the zigzag direction can reach 4.61. Under a bias voltage of 1 V, the maximum photocurrent of 1.8 eV photon energy in the armchair direction can reach 6.71. The maximum photocurrents are in the order of 10−1for both zigzag and armchair directions with 0 V bias. Furthermore, 2D WS2/Mo2CF2vdW heterostructure has a stable and high extinction ratio. These results show that 2D WS2/Mo2CF2vdW heterostructure is a potential candidate material for future optoelectronics in the visible light region. Herein, the photogalvanic effect of 2D WS2/Mo2CF2van der Waals heterostructures under linearly polarized light is studied. The magnitude of photocurrent in the armchair and zigzag directions is affected by the polarization angle. Meanwhile, 2D WS2/Mo2CF2van der Waals heterostructures have high sensitivity to polarized light and a stable extinction ratio.

One dimensional (1-D) nanostructures are envisioned as fundamental building blocks of future electronic, electromechanical, optoelectronic nanodevices and sensors, which will be integrated into nanosystems. We briefly introduce the advantages of 1-D nanostructure in the fabrication of energy conversion devices, followed by the recent developments in device designs, fabrication and some effective approaches for performance enhancement. This review will cover the major progress in three research fields. Firstly, we present the progresses on the fabrication and property modulation of wurtzite nanostructures. Then, we introduce the progresses on the piezotronic properties of wurtzite nano-materials and prototype piezotronic devices, including piezoelectric field effect transistors, piezoelectric diodes, strain sensors and nanogenerators. Finally, the investigations of property degrading and damage of nanomaterials, and functional degrading and failure of the nanodevices will be presented for future electronic applications.

We demonstrated a sort of self-powered vibration sensor based on a triboelectric generator (TEG) using triboelectrification and electrostatic induction effects. The as-prepared TEG delivered an output voltage of 34.06V and short-circuit current density of 22.5mA/m2corresponding to a maximum power density of 0.77W/m2, which was capable of driving five LEDs directly and continuously with working frequency of 50Hz without any rectification circuit or energy storage unit. The vibration sensor has a detection range of 0–500Hz, and high accuracy. Besides, it could realize detection under non-contact mode, which would protect the device and the detected object in operation. Moreover, the stability and repeatability could also be well retained. The TEG based vibration sensor possessed great potential in machines operation monitoring, process control, and security applications in unreachable and access-denied extreme environments.

The electrical service behavior of ZnO nanowires (NWs) with various diameters was investigated by a nanomanipulation technique. The nanodamage and nanofailure phenomena of the ZnO NWs were observed when external voltages were applied. The threshold voltages of the ZnO NWs increased linearly from 15 to 60 V with increasing diameter. The critical current densities were distributed from 19.50 × 106to 56.90 × 106A m–2, and the reciprocal of the critical current density increased linearly with increasing diameter as well. The thermal core–shell model was proposed to explain the nanodamage and nanofailure mechanism of ZnO NWs under an electric field. It can be expected that the investigation on the nanodamage and nanofailure of nanomaterials would have a profound influence on practical applications of photoelectric, electromechanical, and piezoelectric nanodevices.

We report reversible phase transitions of ZnO nanowires subjected to high-pressure diamond anvil cell experiments. It was found that Mn doping obviously changes the elastic stability of ZnO nanowires and leads to low critical pressures of the reversible transitions between wurtzite to rocksalt phases during compression and decompression. First-principles calculations demonstrate that the lower critical pressures caused by Mn doping are associated with the decrease of internal energy difference and the increase of relative volume change between wurtzite to rocksalt phases.

It is highly important to develop high-performance sulfur cathode to solve low areal sulfur loading, shuttling and sluggish conversion of polysulfides for lithium-sulfur batteries. Herein, a three-dimensional (3D) freestanding framework configured with Co nanoparticles and Co-Nxcodoped carbon nanotubes anchored in a carbon foam is synthesized and investigated as a new type of sulfur host. Such an architecture can serve not only as a conductive carbon networks but also as host scaffold for high sulfur-containing electrodes. The hierarchical porous structures cooperated with high density and dispersion multifunctional Co-Nxspecies can efficiently trap and manipulate catalytic conversion kinetics of polysulfides. Benefiting from above characteristics, the designed cathodes exhibit a high capacity (1259 mA h g−1) at 0.1 C and excellent cycling performance with an ultralow decay of 0.038% per cycle over 500 cycles at a high current density of 3 C. Even with a high sulfur loading (7.0 mg cm−2) and lean electrolyte (E/S = 5 μL mg−1) operation, a high areal capacity of 4.34 mA h cm−2is still achieved after 100 cycles at 0.1 C. This work provides a low-cost route for preparation of freestanding cathode materials toward highly efficient lithium-sulfur batteries.

In-doped ZnO nanowires were successfully fabricated by thermal evaporation of a powder mixture of Zn, In2O3, and graphite. Field emission of individual In-doped and pure ZnO nanowire was observed in situ by a transmission electron microscopy. The results show that In-doped ZnO nanowires showed an enhanced field emission properties. First-principle density functional calculations were performed to calculate the electronic structure of the In-doped and pure ZnO in order to explain the observed field emission properties. A two-band field emission mechanics was proposed to explain the enhanced field emission from n-type doping.