▎ 摘　　要

Magnetic adsorbent combining graphene and chitosan have exhibited encouraging application in wastewater remediation. Herein, magnetic graphene oxide-chitosan nanohybrid (MGC) was readily obtained via synchronous reduction-precipitation under a mild experimental condition and utilized as adsorbent to remove aqueous Hg(Pi). The interaction mechanism between MGC and Hg(Pi) was unveiled via spectroscopic analyses, adsorption fittings and the hard-soft acid-base theory. Results present, 95 % of -NH2 in chitosan was transformed into-C(=O)NH- via amidation with -OH, enabling the outperfor-mance of MGC over any single phase. MGC efficiently adsorbs 339.82 mg.g 2803;1 of Hg(Pi) in 8 min, during which the counterions in Hg(NO3)(2)center dot H2O were simultaneously adsorbed via chemical interaction featured by electron donation. Specifically,-C(=O)NH-, C-O and O-2(-) contribute to Hg(Pi) uptake, while Fe(III), Fe (Pi) contribute to NO3- uptake. This work may provide inspiration for developing efficient adsorbent based on magnetic graphene oxide-chitosan. (c) 2022 Elsevier B.V. All rights reserved.