Investigation of Cu heteroatoms and Cu clusters in Fe-Cu alloy and their special effect mechanisms on the Fenton-like catalytic activity and reusability

Fe/Cu bimetallic materials are promising Fenton-like catalysts to deal with the increasing environmental pollution. However, it remains a great challenge to prepare conveniently desirable Fe/Cu co-catalysts with brilliant catalytic efficiency and simultaneously reveal their co-catalytic mechanism. Herein, we report a facile approach of generating Fe-Cu alloys with outstanding Fenton-like catalytic performance via a straightforward electrodeposition method. The degradation ability of Fe-Cu alloy mainly comes from Fe2+/H2O2 reaction, while the Cu components including the Cu heteroatoms in Fe lattice and the independent Cu clusters in alloy play a notable assistant role. Experiments and density functional theory (DFT) calculations indicate that the Cu heteroatoms enhance the capacity of adjacent Fe atoms for the adsorption of H2O2 to generate more •OH, while the independent Cu clusters suppress the surface passivation of catalyst for improving the reusability in cycle experiments. Our study will promote the industrial application of bimetallic Fenton-like catalysts for water treatment. [Display omitted] •Hierarchical Fe-Cu alloys were prepared by electro-deposition method.•Fe-25Cu possesses excellent catalytic activity and reusability.•The Cu components in Fe-Cu alloy are Cu heteroatoms and independent Cu clusters.•Cu heteroatoms are responsible for the catalytic activity via enhancing H2O2 adsorption.•Independent Cu clusters boost the reusability via suppressing the passivation layer.