“…The intensities of the bands at 1549, 1514, and 1420 cm −1 related to amine (N–H) groups (Weißpflog et al 2021 ) and 1381 cm −1 related to C─H bending vibration increased after the biosorption of RY2 onto ZM@GFC. The absorption bands at 1381 cm −1 (C─H bending) (Akar et al 2021 ), 1238 cm −1 (C–O/C–O–C stretching or CH 2 wagging) (Huang et al 2018 ; Zhang et al 2011 ), and 1155 cm –1 (stretching vibrations of C–O of alcohols) (Liu et al 2022 ) also shifted to 1379, 1248, and 1161 cm −1 , respectively, after the dye biosorption process. These results confirmed the biosorption of RY2 at all the mentioned binding sites on the ZM@GFC surface.…”