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Over the past decade, wood‐derived materials have attracted enormous interest for both fundamental research and practical applications in various functional devices. In addition to being renewable, environmentally benign, naturally abundant, and biodegradable, wood‐derived materials have several unique advantages, including hierarchically porous structures, excellent mechanical flexibility and integrity, and tunable multifunctionality, making them ideally suited for efficient energy storage and conversion. In this article, the latest advances in the development of wood‐derived materials are discussed for electrochemical energy storage systems and devices (e.g., supercapacitors and rechargeable batteries), highlighting their micro/nanostructures, strategies for tailoring the structures and morphologies, as well as their impact on electrochemical performance (energy and power density and long‐term durability). Furthermore, the scientific and technical challenges, together with new directions of future research in this exciting field, are also outlined for electrochemical energy storage applications.

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The large‐scale fabrication of efficient and inexpensive bifunctional catalysts is highly desirable but very challenging for oxygen reduction reaction and oxygen evolution reaction (ORR–OER) in metal–air batteries. Here, a facile and scalable approach for the fabrication of hierarchically porous air electrode consisting of cobalt nanoparticles embedded in bamboo‐like nitrogen‐rich carbon nanotubes (Co/N@CNTs), which are in situ grown onto the surface of carbon nanotube macrofilm (CNMF) through a catalytic growth of crosslinked carbon nanotubes is reported. The resulting hybrid macrofilm (Co/N@CNTs@CNMF) can be directly used as a freestanding air electrode without adding any binder or addivities. More importantly, when incorporated in a zinc–air battery (ZAB), the Co/N@CNTs@CNMF electrode demonstrates drastically enhanced ORR and OER activity while maintaining excellent durability during cycling. Further, when it is used to assemble an all‐solid‐state ZAB, the cell also displays excellent mechanical flexibility, implying promising perspectives as power sources for wearable electronics.