The synthesis of TiO2 nanoflowers and their application in electron field emission and self-powered ultraviolet photodetector

TiO2 nanoflowers composed of nano-needles had been synthesized by hydrothermal method and their field electron emission properties were studied for the first time, which exhibit a low turn-on field of 4.76 V/μm, a high field enhancement factor of up to 5216. This performance was better than that of the as reported TiO2 nanostructure arrays. The efficient field emission behaviours were found to be not only attributed to their 3 dimensional structures of the nanoflowers but also related to their nano-needle morphology. Besides, self-powered ultraviolet photodetector based on TiO2 nanoflowers had been fabricated and it showed an obvious response trend in both UV and visible regions with good repeatability and stability, also the photoresponse mechanism at zero bias had been depicted through the energy band theory.