Multifunctional nanocatalysts of Au@FeO/m-SiO yolk@shell hybrids had been developed through a template-assisted synthesis, where FeO nanoparticles (∼12 nm) and m-SiO shells were sequentially assembled on surfaces of Au/SiO core/shell templates, followed by selective etching of the inner SiO cores, leading to the formation of Au@FeO/m-SiO yolk@shell hybrids. The FeO nanoparticles were implanted in the inner surfaces of m-SiO shells with partially exposed surfaces to the inner cavity. The novel design not only ensures a high surface area (540.0 m/g) and saturation magnetization (48.6 emu/g) of the hybrids but also enables interaction between Au and FeO nanoparticles. Catalytic tests toward the reduction of 4-nitrophenol in the presence of NaBH indicated that Au@FeO/m-SiO yolk@shell nanocatalysts not only showed high stability and recyclability but also maintained improved catalytic activity as a result of the synergetic effect resulting from Au and FeO interactions.

Noble metal−Fe 3 O 4 dumbbell-like nanoparticles have aroused considerable attention because of their high potential as heterogeneous nanocatalysts. The designed synthesis of the advanced architecture of noble metal−Fe 3 O 4 dumbbell-like nanoparticles with both improved catalytic activity and stability is still a challenge. Herein, through the combination of yolk@shell and dumbbell-like nanostructures, dumbbell-like Pt−Fe 3 O 4 nanoparticles encapsulated in N-doped carbon hollow nanospheres (Pt−Fe 3 O 4 @N-carbon) as a special yolk@ shell nanostructure were developed. In comparison with Pt−Fe 3 O 4 dumbbell-like nanoparticles, Pt−Fe 3 O 4 @N-carbon yolk@shell nanoparticles showed improved catalytic activity and stability toward the liquid-phase 4-nitrophenol reduction and β-ionone oxidation, making them a promising candidate for catalysis applications.

Developing nonprecious electrocatalysts for efficient oxygen reduction reactions (ORR) has aroused increasing interest recently. Doped nanocarbons derived from conducting polymers have emerged as a competitive class of nonprecious‐metal catalysts for the ORR because of their promising catalytic activities, long‐standing stability, and particularly low‐cost and facile preparation at a large scale via simple approaches. This review summarizes the recent progress of the preparation and application as ORR electrocatalysts of heteroatom doped nanocarbons derived from conducting polymers, and transition metal and heteroatom‐codoped nanocarbons from conducting polymers and metal salts. Finally, the challenges and further development of this field are also discussed.

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Understanding and manipulation of catalytic enantioselectivity have emerged as a paramount challenge for decades. Inspired by nature, nanozymes with enantioselectivity have been designed. However, the role of the spatial arrangement interplayed in enantioselective catalysis is rarely paid attention, let alone the manipulation of enantioselectivity switch under this context. Herein, the supramolecular chiral nanozymes composed of P/M‐polyaniline (P/M‐PANI) nanotwists and Fe3O4 nanoparticles without any chiral molecules are constructed. Taking the catalytic oxidation of 3,4‐dihydroxy‐d / l‐phenylalanine (d / l‐DOPA) as a model reaction, P‐PANI–Fe3O4 nanozymes are demonstrated to show better catalytic efficiency toward D‐DOPA, whereas M‐PANI–Fe3O4 nanozymes show preference to L‐DOPA. Intriguingly, through the simple modulation of the Fe3O4 nanoparticle density on P/M‐PANI–Fe3O4, the unprecedented enantioselectivity switch of the as‐designed nanozymes is achieved. Moreover, the select factors of P/M‐PANI–Fe3O4 toward d / l‐DOPA are determined to be significantly larger than that of commonly used chiral ligands (such as d / l‐phenylalanine)‐modified Fe3O4 nanozymes, indicating the superiority of spatial arrangement‐dominated supramolecular chirality over molecular chirality in enantioselectivity. This finding discloses the role that the spatial arrangement‐directed chiral scaffolds interplay in the enzymatic catalytic process and open a new avenue for the facile design of smart nanozymes with controlled enantioselectivity.