Pseudocapacitive materials encapsulated in conductive carbon matrix are of paramount importance to develop energy storage devices with high performance and long lifespan. Here, via simple laser‐scribing, the Mn‐based metal–organic framework [EG‐MOF‐74(Mn)] is transformed into pseudocapacitive hybrid MnO/Mn7C3 encapsulated in highly conductive graphitic carbon. It is revealed that the rapid carbothermic reduction of MnO (C + MnO → C′ + Mn7C3 + CO) leads to the formation of the intermediate pseudocapacitive MnO/Mn7C3 and the concurrent catalytic graphitization of disordered carbon. This reaction produces a new type of pseudocapacitive material in the form of MnO/Mn7C3 fully embedded in highly conductive graphitic carbon. Thanks to the synergistic effect of the MnO/Mn7C3 nanoparticles and the graphitic carbon, the composite exhibits a high specific capacitance of 403 F g−1 with excellent stability. Asymmetric coin‐cell supercapacitors based on the composite demonstrate high energy (29.2 Wh kg−1) and power densities (8000 W kg−1) with a long lifespan. Prototypes of flexible paper‐based supercapacitors made of the composite also show great potential toward applications of flexible electronics.

The facemask is a potential device to protect yourself and others against pandemics, such as coronavirus disease 2019 (COVID-19), and adding a functional filter to the facemask could offer extra protection against infectious microbes (such as bacteria and viruses) to the wearer. Here, we designed and fabricated an always-on photocatalytic antibacterial facemask, which comprised a reusable polypropylene filter layer coated with the photocatalytic laminated ZnO/TiO 2 bilayer and a separate UV-LEDs layer to supply UV whenever necessary. The fabricated photocatalytic filter was able to be directly inserted into the reusable facemask together with the UV-LEDs layer. This facemask could be used repeatedly and sustainably anytime and anywhere regardless of solar illumination. The photocatalytic filter exhibited an excellent photocatalytic antibacterial effect likely due to recombination suppression of electrons and holes of ZnO/TiO 2 bilayer and wetting transition from hydrophilic to superhydrophilic state on the surface of the filter. Thanks to the kirigami pattern in both photocatalytic filter and UV-LEDs layer, full-face covering, breathability, flexibility, and the snug fit are believed to be improved. Although further in-depth studies are still needed and there is a long way to go, we expect our design idea on the facemask to be considered in various fields.

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