InGaAs is an important bandgap-variable ternary semiconductor which has wide applications in electronics and optoelectronics. In this work, single-crystal InGaAs nanowires were synthesized by a chemical vapor deposition method. Photoluminescence measurements indicate the InGaAs nanowires have strong light emission in near-infrared region. For the first time, photodetector based on as-grown InGaAs nanowires was also constructed. It shows good light response over a broad spectral range in infrared region with responsivity of 6.5 × 103 A W−1 and external quantum efficiency of 5.04 × 105 %. This photodetector may have potential applications in integrated optoelectronic devices and systems.

•High quality few-layer WO3 nanosheets were synthesized via CVD route.•The UV photodetectors were fabricated based on these few-layer WO3 nanosheets.•The photosensitive properties were studied upon UV irradiation.•The UV photodetectors show excellent optoelectronic performance.High quality few-layer WO3 nanosheets were synthesized via chemical vapor deposition (CVD) route. The high-performance UV photodetectors were successfully fabricated based on these few-layer WO3 nanosheets, showing excellent optoelectronic performance with high sensitivity (293 A/W), fast response speed(40 ms), high on/off ratios(2000), high external quantum efficiency (EQE, 997%), excellent stability, reversibility. These unique characteristics of the WO3 photodetectors pave the way for the fabrication of multifunctional and high performance flexible photodetectors based on the layered semiconductor materials.

In this work, we synthesized high-quality InAs nanowires by a convenient chemical vapor deposition method, and developed a simple laser heating method to measure the thermal conductivity of a single InAs nanowire in air. During the measurement, a focused laser was used to heat one end of a freely suspended nanowire, with its other end embedded into a carbon conductive adhesive. In order to obtain the thermal conductivity of InAs nanowires, the heat loss in the heat transfer process was estimated, which includes the heat loss through air conduction, the heat convection, and the radiation loss. The absorption ratio of the laser power in the InAs nanowire was calculated. The result shows that the thermal conductivity of InAs nanowires monotonically increases from 6.4 W m−1 K−1 to 10.5 W m−1 K−1 with diameters increasing from 100 nm to 190 nm, which is ascribed to the enhanced phonon-boundary scattering.