Ultrahigh Stability of Wearable Photodetector Using Zirconium Metal‐Organic Framework Enabling In Situ and Continuous Monitoring of Ultraviolet Radiation Risk

Abstract

Abstract Zirconium‐benzenedicarboxylate (ZrBDC) is a remarkably stable metal‐organic framework with a broadband UV absorption that would offer numerous applications related to UV detection. However, the integration of a continuous and densely packed ZrBDC film with the controllable thickness into optoelectrical devices suffers from time‐consuming and complicated fabrication of ZrBDC thin film. In this study, a facile liquid‐phase epitaxy method is introduced by adopting sequential and continuous layer‐by‐layer spin‐coating technique to fabricate the high‐quality ZrBDC thin film. The structural, optical, and electrical properties of the as‐prepared ZrBDC thin film are characterized by X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, ultraviolet‐visible spectroscopy, photoluminescence spectroscopy, space charge limited current, and Mott‐Schottky measurement. When ZrBDC is used as an efficient photo‐absorber layer for a visible‐blind UV photodetector, the device exhibits a specific detectivity of 7.85 × 10 10 Jones and rise/fall time of 80/150 ms at zero bias. Furthermore, the device reveals outstanding stability with nearly constant photoresponse during 19 h‐exposure to UV illumination and after storing for 2 months, along with excellent tolerance under high operating temperature and bending strain. For practical applications, the facile estimation of UV level under sunlight is demonstrated using a wearable UV detector based on ZrBDC.