AUTHOR= Frontiers Editorial Office TITLE=Expression of concern: Kinetic and equilibrium study of graphene and copper oxides modified nanocomposites for metal ions adsorption from binary metal aqueous solution JOURNAL=Frontiers in Chemistry VOLUME=12 YEAR=2024 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2024.1450335 DOI=10.3389/fchem.2024.1450335 ISSN=2296-2646