Single‐atom catalysts have drawn considerable attention because of their unique catalytic properties. However, the high surface energy of single atoms restricts their fabrication and creates significant challenges for further developments. In order to overcome this problem, metal organic framework (MOF)‐derived carbon materials can be served as ideal supports to anchor atomically dispersed metal atoms, due to their tunable particle size and shape features, by providing high surface area, porosity, thermal, and chemical stability. This review highlights the recent advances in i) different types of construction strategies for MOF‐derived carbon‐supported single‐atom catalysts, and ii) the catalytic applications of these MOF‐derived carbon‐supported single‐atom catalysts. Further, this review offers a valuable insight into the current challenges and future opportunities for MOF‐derived carbon‐supported single‐atom catalysts.

We report a surprising discovery that Prussian blue (PB) can be employed as a highly sensitive and background-free resonant Raman reporter. Conventional Raman reporters show multiple spectral bands in the fingerprint region, which are generally overlapped with those from dominant endogenous biomolecules, and are thus difficult to be separated. Herein, we found that PB only possesses a strong and sharp single-band in the cellular Raman-silent region, where no Raman signals from biological species were observed. Therefore, the Raman spectra from PB and endogenous biomolecules are completely resolved without resorting to complicated spectral unmixing. Moreover, PB holds a strong UV-vis absorption band between 500 and 900 nm, which is resonant with the incident detection lasers, providing extremely high sensitivity. Through assembly of PB onto plasmonic cores, a new surface-enhanced resonance Raman scattering (SERRS) probe was achieved with a high signal-to-background ratio (SBR). We demonstrated the performance of the PB-based SERRS tags for high-sensitivity immunoassay and cancer cell imaging.

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The development of inexpensive and highly efficient nonprecious metal catalysts to substitute Pt in the alkaline oxygen reduction reaction is an appealing idea in the energy field. Herein, a Mn oxygen reduction electrocatalyst with a half‐wave potential (E1/2) as high as 0.910 V under an alkaline oxygen reduction reaction process is developed, and the dynamic atomic structure change of the highly efficient Mn single‐atomic site is investigated using operando X‐ray absorption spectroscopy. These results demonstrate that the low‐valence MnL+N4 is the active site during the oxygen reduction process. Density functional theory reveals that facile electron transfer from MnL+N4 to adsorbed *OH species plays a key role in the excellent electrocatalytic performance. Moreover, when assembled as the cathode in a zinc–air battery, this MnN4 material shows high power density and excellent durability, demonstrating its promising potential to substitute the Pt catalyst in practical devices.