As a kind of n-type semiconductor, W18O49 nanowire has good light absorbing ability and photothermal conversion performance. And it can shield ultraviolet light effectively. Therefore, W18O49 nanowire has broad application prospects in the preparation of ultraviolet photodetector.

Ultraviolet photodetector is a kind of sensor that converts electromagnetic radiation signal into electrical signal through the photoelectric effect. It plays an important role in many fields such as missile tracking, ozone monitoring, flame detection, imaging techniques and lightwave communications. 

 

One-dimensional nanostructures of high-performance oxides are considered as s a class of potential optoelectronic materials. And W18O49 nanowire has attracted much attention with its strong absorbing ability of ultraviolet light.

 

W18O49 nanowire can be applied in the preparation of optoelectronic device and ultraviolet photodetector. And the related preparation process is as follows:

 

W18O49 nanowire is synthesized on ITO glass substrate by thermal evaporation of tungsten trioxide powders without catalysts or additives. To fabricate a single-nanowire detector, seven parallel Ti/Au (10 nm/150 nm) electrodes spaced about 2 μm apart are fabricated with photolithography on a Si substrate with a 500 nm SiO2 layer. The as-prepared W18O49 nanowire is dispersed in deionized water by ultrasonic. An AC voltage with a frequency of 1 MHz and a peak to peak voltage Vp–p=16 V is applied between the two electrodes when a droplet of the W18O49 nanowire suspension is dropped to cover the electrodes area using a micropipette. A fast thermal annealing at 300°C is carried out in N2 atmosphere for 2 minutes to form the ohmic contacts between the electrodes and nanowire.

 

The optoelectronic device based on single W18O49 nanowire has strong ultraviolet photosensitivity. When this kind of optoelectronic device is applied in ultraviolet photodetector, the ultraviolet photodetector will exhibit superior performance in sensitivity and reversibility. W18O49 nanowire is an ideal material for preparing ultraviolet photodetector.