Fig. 2.

Morphological and structural characterizations of natural wood and all-wood hydrogels. SEM images of the natural wood: a the top-view SEM image and b its magnified image, and c the side-view SEM image of natural wood. SEM images of the all-wood hydrogel: d the top-view SEM image and e its magnified image, f the side-view SEM image and g its magnified image. h, i Confocal images showing the penetration of PVA into the microchannels of the all-wood hydrogel. Scale bar, 100 μm. j SAXS pattern of the prepared all-wood hydrogel. k FTIR spectra and l XRD patterns of the PVA, relignified wood, and all-wood hydrogel