Amorphizing of Ag Nanoparticles under Bioinspired One-step Assembly of Fe3O4-Ag/rGO Hybrids via Self-redox Process with Enhanced Activity

Efficient and reusable nanocatalysts fabricated via a facile assembly are highly desirable for the cost-effective hydrogenation reduction. Inspired by a fishing process with a fishnet, multifunctional nanostructured catalysts are rationally designed to combine interesting features via the self-redox assembly of Fe 3 O 4 -Ag composites on reduced graphene oxide (rGO) (Fe 3 O 4 -Ag/rGO). In detail, Fe 3 O 4 nanoparticles (NPs) endow the ternary hybrids with superparamagnetism (21.42 emu g −1 ), facilitating catalysts to be separated from the reaction system. rGO could provide electron transfer pathways, enhancing catalytic activity. More interestingly, GO and Ag + could behave as oxidants to oxidize Fe 2+ for the in situ assembly of Fe 3 O 4 -Ag/rGO without any addition of reductant/oxidant or organic solvents, and AgNPs endow the ternary hybrids with excellent catalytic behaviour. Meaningfully, the bioinspired process enables the ternary hybrids to possess more abundant micro−/nanopores, larger surface area, and more amorphization. They exhibit exceptional catalytic performance, and could be recycled with excellent activity by means of convenient magnetic separation (at least 7 times). Moreover, the ternary hybrids could degrade methylene blue under UV light due to different valence states of Fe in Fe 3 O 4 . Therefore, the proposed bioinspired assembly and structure design for hierarchical catalysts would pave a promising way to assemble other catalysts.