Real-Time Quantitative Detection of Ultraviolet Radiation Dose Based on Photochromic Hydrogel and Photo-Resistance

Real-time quantitative detection of ultraviolet (UV) radiation dose is vitally important in life and industry. Herein, we report a novel system for real-time quantitative detection and monitoring of UV radiation dose based on photochromic hydrogel and photo-resistance. The UV radiation probe is composed of a UV-responsive poly(N,N-dimethylacrylamide)-ammonium molybdate tetrahydrate hydrogel that rapidly and significantly changes color responding to UV radiation dose, a red filter that instantaneously amplifies the UV-radiation-induced color change signal, and a photo-resistance that instantaneously transforms the color change signal into electric resistance signal. Based on the quantitative relationship between electric resistance and UV radiation dose, real-time quantitative detection of UV radiation dose can be effectively achieved. By further combining the UV radiation probe with a specially designed printed circuit board (PCB), real-time monitoring of UV radiation dose with automatic alarm system is demonstrated for warning and terminating of excessive UV radiation. Such an efficient real-time quantitative detection system for UV radiation dose is highly promising in various applications, such as dermatological treatment, industrial production, and photocatalytic sterilization with UV rays. Furthermore, the proposed strategy provides a universal method to develop novel photodetectors using other photochromic materials and may inspire novel detection and monitoring instruments.