Recent advances in fluorescent materials innovation and film‐based sensing application

Film‐based fluorescent sensors (FFSs), an “IUPAC Top Ten Emerging Technology in Chemistry 2022,” are attracting growing interest for applications in public safety, environmental monitoring, and disease diagnosis, driven by their high sensitivity, rapid response, and facile integration. The core of FFSs lies in their engineered sensing films, where efficient molecular channels within the film's architecture dictate key performance metrics like response/recovery speed and signal‐to‐noise ratio. Thus, the choice of fluorophores and fabrication techniques is paramount for controlling the film's internal structure. This review surveys innovative strategies for constructing porous sensing films, focusing on: using nonplanar fluorophores to build intrinsic pores; self‐assembling low‐molecular weight gelators into 3D gel networks; incorporating framework materials for ordered, low‐defect topological structures; and applying interfacial polymerization to create high‐surface‐area nanofilms. We then explore how these high‐performance FFSs detect targets from explosives and volatile organic compounds to chemical residues and humidity. The review concludes with an analysis of current challenges and a perspective on future paths, providing a roadmap to advance FFSs from laboratory to real‐world use.