The phosphorescence nanocomposite thin film with rich oxygen vacancy: Towards sensitive oxygen sensor

Organic room temperature phosphorescent (ORTP) materials provide an exciting research direction for phosphorescent oxygen (O 2 ) sensors due to their high sensitivity and rapid response to O 2 . However, most pure ORTP materials are tightly-packed aromatic compound crystals in a face-to-face manner, which largely prohibits effective O 2 diffusion for sensing. Thus, how to solve this contradiction still faces huge challenges. Here, the use of organic phosphorescent indicator carbon dots (CDs), inorganic matrix layered double hydroxides (LDHs) and polymers (PVA) successfully prepared an ultra-long RTP composite film whose phosphorescence decay intensity is linearly related to O 2 concentration. More importantly, the use of the abundant O 2 defects (Vo) on the surface of the inorganic matrix LDHs to adsorb O 2 , which further accelerates the phosphorescence quenching of the thin film and improves the O 2 response. This strategy will provide the possibility to develop high-sensitivity phosphorescent O 2 sensors from a new perspective. .