It is enough to mechanically grind or sonicate the TEMPO-oxidized cellulose to liberate the oxidized cellulose fibers into a homogeneous, highly viscous suspension of 3-5 nm cellulose nanofibrils.25 The electrostatic repulsions between the cellulose fibrils bearing the COO- groups ensures good dispersion and high stability of the nanofibrils in solution. Repulsion among the carboxylated fibers, furthermore, causes a decrease in the electricity consumed to power the mechanical fibrillation process.