Fig. 1: Concept and interaction chemistry by stereoisomers.

a Schematic illustration of the multifunctional effects of the FU additive in ZMBs. White, gray, and red spheres represent H, C, and O atoms, respectively. b Binding energy of Zn2+ with H2O, FU−, FU2−, MA−. Pink, gray, light blue, and dark blue spheres represent H, C, O, and Zn atoms, respectively. c Radial distribution functions and corresponding coordination numbers of Zn2+–O (FU/MA) in ZnSO4/FU and ZnSO4/MA. d Electrostatic potential maps of Zn2+(H2O)4FU2− and Zn2+(H2O)5MA−. Pink, gray, light blue, and dark blue spheres represent H, C, O, and Zn atoms, respectively. e FT-IR spectra, f 1H NMR spectra, and g 13C NMR spectra of ZnSO4, ZnSO4/FU and ZnSO4/MA.