Ag-Nanoparticle-Coupled UV-Responsive Gelatin Nanofiber Photodetectors

Abstract

In this era of environmental protection and performance, the development of organic photodetectors is booming. The hydrogel material is beginning to attract attention because of its characteristics such as plasticity and ecofriendliness. However, it is still a challenge to achieve a high-speed response in biophotodetectors. Herein, the development of an organic one-dimensional nanostructured photodetector is proposed through rotary-jet injection of gelatin fibers incorporated with silver nanoparticles (Ag NPs). The variation in the photoelectric properties of thin-film, fibrous structures with different diameters of approximately 40 μm and 400 nm has been investigated. In particular, the gelatin–Ag NPs fiber photoreceptor with a diameter of about 400 nm improved the light-to-dark current ratio by up to 28000% higher than the film structure, with rise and decay times of only 0.23 and 0.56 s. In addition, the nanostructure effectively boosts the photocurrent and suppresses the dark current because of its confining domains. The Ag NPs within the gelatin nanofibers produce localized surface plasmon resonance in the UV-illumination environment, enhancing the light absorption of the photosensitive layer, which contributes directly to the increase in the rate of excitons. The novel structure of the hybridized gelatin nanofibers incorporating silver nitrate has offered the promising potential for organic photodetectors.