Masuko refining of unbleached kraft birch pulp has been noted to result in more thorough fibrillation than the refining of its bleached counterpart. This result is observed through different fractionation behavior of once refined pulps and is further supported by different relative changes in pulp viscosity. The formation of mechanoradicals during refining is observed with electron paramagnetic resonance spectroscopy, and the role of lignin and hemicelluloses [quantified using kappa number determination and UV resonance Raman (UVRR) spectroscopy] in the progress of refining is discussed. Lignin, a known antioxidant, is capable of stabilizing radicals, which could potentially counteract recombination reactions between highly reactive cellulose radicals. On the other hand, lignin’s ability to promote fibrillation could also lie in its amorphous nature and not solely in its antioxidant characteristics. Furthermore, bleaching removes not only lignin but also hemicelluloses, which affects both the charge density and the structure of the fiber material, and this is another likely contributor to the easier fibrillation of lignin-containing pulps.

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In this recent decade, great interest has risen to develop metal-free and cheap, biomass-derived electrocatalysts for oxygen reduction reaction (ORR). Herein, we report a facile strategy to synthesize an electrochemically active nanocarbon material from the renewable and biological resource, wood biomass. The ORR activity of the catalyst material was investigated in 0.1 M KOH solution by employing the rotating disc electrode method. Scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy were employed to obtain more information about the catalyst material’s morphology and composition. The material exhibits outstanding electrocatalytic activity with low onset potential and high current density, similar to that of a commercial Pt/C catalyst in an alkaline medium. The results clearly ascertain that wooden biomass can be easily transformed into novel carbon nanostructures with superior ORR activity and possibility to be used in fuel cells and metal–air batteries.