Adsorbent Adsorption capacity for Cu2+ (mg/g) References Modified silica aerogel 90.1 [27] Chitosan-coated MNPs modified with alpha-ketoglutaric acid 96.15 [28] Amino functionalized Fe3O4 @ SiO2 core–shell NPs 29.85 [29] Amphiphilic PMMA/PEI core–shell nanoparticles 14 [30] Crosslinked chitosan with epichlorohydrin 35.46 [31] Hydroxyapatite nanoparticles 36.9 [32] Fungal biomass immobilized within a loofa sponge (FBILS) 98.9 [33] PVA/p(AAm-NIPAm) core-shell nanogels 126 This work

Table 1: Comparison of adsorption capacities for Cu2+ of various adsorbents with PVA/p(AAm-NIPAm) nanogels adsorbent.