Fluorescence Lifetime Imaging Microscopy: Advances in Materials Science Research

Controlling formation dynamics and tuning micro- or nanoscale structures are crucial to designing materials with desired properties for specific applications. Thus, visualization of the structures and probing of the in situ formation mechanisms of molecular materials are quite important, although challenging. Recently, fluorescence lifetime imaging microscopy (FLIM) has emerged as a valuable complementary, robust, and noninvasive technique along with conventional imaging tools to unravel the nanoscale morphology and dynamics of fluorescent or fluorophore-tagged molecular materials. This Review emphasizes the growing importance of FLIM in exploring the salient aspects of various materials, including semiconductor nanocrystals, molecular self-assembly, polymers, and metal–organic frameworks. The fundamental features of FLIM and its applications decipher the dynamic self-assembly process, the growth kinetics of and mechanistic insights into polymers, and the phase purity in metal–organic frameworks. Additionally, this work also highlights the use of FLIM as a complementary tool along with intensity-correlation techniques in photoluminescence blinking and photon antibunching to resolve many unreciprocated facts in the field of semiconductor nanocrystals. Beyond presenting up-to-date knowledge in the field, we outline the potential future directions of FLIM for developing different materials and improving existing ones. This advancement paves the way for further opportunities in materials science research and applications.