Fig. 4

AFM amplitude images,3D images and height distribution images (from left to right): a the untreated RS presented a smooth surface; b RS-Fenton surface became noticeably rough with the appearance of highlighted hydrophilic hemicellulose sites and hydrophobic lignin droplets (20–100 nm, pointed out with the arrow); c RS-Fenton + B-8, the globular shapes of the deposited lignin decreased