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Tailoring the photoluminescence (PL) of semiconductors through spatiotemporal manipulation of dynamics of photoexcited carriers is of paramount importance for understanding the emitting mechanism and developing high‐performance devices. Herein, fluorescence recovery after photobleaching (FRAP) microscopy, a powerful tool in biology, is first utilized to simultaneously manipulate and monitor the dynamics of photoexcited carrier in attractive 2D transition metal dichalcogenide monolayers (1L‐TMDs). This allows on‐demand access to the PL dark state of 1L‐TMDs, based on the triggered exciton–exciton annihilation by pump beam‐initiated photodoping. Using a 0.7‐µm‐diametered pump laser, the PL dark region can be facilely tailored from ≈0.5 to ≈5 µm over a 10‐µm‐1L‐WS2 flake. An interesting photoinduced dedoping effect in 1L‐TMDs after photodoping is discovered by FRAP, which has not been observed before and might account for the non‐blinking emission of 1L‐TMDs. The revealed mono‐exponential photo‐dedoping can also be kinetically tailored by ≈170‐fold (k: 0.11–19.00 s‐1) by humidity, power of incident laser and type of 1L‐TMDs. This study demonstrates the power of FRAP microscopy in exploring the effect of photoexcited carrier dynamics on the PL property of semiconductors, holding promises for understanding light‐emitting mechanism and optimizing operational parameters for optoelectronic devices. [ABSTRACT FROM AUTHOR]

Metal aerogels (MAs) are emerging all‐nanometal‐structured self‐standing porous materials featuring exceptional performances in diverse fields. They have recently been adopted as 3D surface‐enhanced Raman scattering (SERS) substrates, while the less utilization of the unique porous structure leads to limited performance. Here, a fascinating compression‐mediated regulation strategy is presented to largely boost the SERS performance of Au–Ag aerogels. By gently pressing, both the density of hot spots and the inter‐ligament distance can be efficiently modulated, thus enabling to flexibly manipulate the SERS properties of MAs. On this basis, a record‐high misfocus tolerance (∼8.8 mm), low detection limit (down to 0.1 nM), high stability (>1 month), reusability, and multiplex detection ability are concurrently realized. This study may point out a new direction for engineering 3D SERS substrates with tunable and exceptional performance. [ABSTRACT FROM AUTHOR]