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A series of Ru‐based catalysts have been developed for the hydrogen evolution reaction (HER) by the facile impregnation of copious and eco‐friendly bacterial cellulose (BC) with Ru(bpy)3Cl2 (bpy = 2,2′‐bipyridine) followed by pyrolysis. After the oxidation and molecular recomposition processes that occur within the BC precursors during pyrolysis, sub‐2 nm Ru nanoparticles (NPs) and atomic Ru species confined within surface‐oxidized N‐doped carbon nanofibers (CNFs) can be observed in the derived catalysts. The surface oxidation of CNFs leads the derived catalysts with super hydrophilicity and water‐absorbing capacity, and also provides dimensional confinement for the nanoscaled and atomic Ru species. With these added structural advantages and the component synergy, the derived catalysts show superior HER activities, for which the overpotentials are as low as 19.6 mV (1 m KOH) and 55.0 mV (0.5 m H2SO4) for the most active case at the current density of 10 mA cm−2. Moreover, superior HER activity can be also achieved for the catalysts derived with a wide range of Ru loadings. Finally, the influence of Ru NP size on HER activity is investigated by density functional theory simulations. This method provides a reliable protocol for preparing highly active HER catalysts for scale‐up applications.

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N-doped and shape-controlled porous monolithic carbon (PMC) was easily fabricated and displayed excellent electrochemical performance as an electrode for supercapacitors.

Hierarchically porous activated carbons (ACs) derived from apricot shell (AS), which is a low-cost and abundant carbon source from a renewable and sustainable biomass waste, were prepared by a green and facile approach via carbonization followed by steam activation and applied to electrodes for symmetric supercapacitors (SCs). The as-obtained AC possessed large surface area and developed porosity with hierarchical pore texture, leading to the specific capacitance of 38.3 F g−1 for an AC//AC symmetrical SC in 20 wt% H2SO4 aqueous electrolyte. Moreover, the assembled AC//AC SC exhibited superior cycling life stability with 99% retention after 6000 cycles at 5 A g−1. These results demonstrate that the present facile, low-cost, and environmentally friendly synthetic strategy for hierarchical ACs from AS can promote the utilization and conversion of AS to high value-added industrial products as well as commercial applications in energy storage devices.