Montan˜oleyva et al. have extracted cellulose from wheat straw using chemical methods. Cellulose nanofibers are fabricated by electrospinning with TFA as the solvent. Fig. A shows the untreated wheat straw (image A), which is composed of cellulose fiber bundles, the cellulose fibers after chemical treatment (image B), and the electrospun cellulose nanofibers with the average diameter of 270± 97 nm (image C).
Qi et al. have dissolved cellulose in a mixture of NaOH and urea and found that spherical particles with diameters of 100-300 nm are obtained by electrospinning instead of fibers. The addition of high-molecular-weight polyethylene glycol or PVA auxiliary into the mixture of NaOH and urea reduces the viscosity of the cellulose solution and increased the spinnability of the cellulose, and thereby bicomponent nanofibers with an average diameter of 400 nm are produced.