Hydrodynamic synthesis of Fe2O3@MoS2 0D/2D-nanocomposite material and its application as a catalyst in the glycolysis of polyethylene terephthalate

We report a fast and simple synthesis of Fe₂O₃@MoS₂ 0D/2D-nanocomposite material using a Taylor–Couette flow reactor. A Taylor–Couette flow with high shear stress and mixing characteristics was used for fluid dynamic exfoliation of MoS₂ and deposition of uniform Fe₂O₃ nanoparticles, resulting in a Fe₂O₃@MoS₂ in the form of 0D/2D-nanocomposite material. Using Taylor–Couette flow reactor, we could synthesize Fe₂O₃@MoS₂ 0D/2D-nanocomposite material at a rate higher than 1000 mg h⁻¹ which is much higher than previously reported production rate of 0.2–116.7 mg h⁻¹. The synthesis of Fe₂O₃@MoS₂ nanocomposite was achieved in an aqueous solution without thermal or organic solvent treatment. Exfoliated MoS₂ nanosheets show an average thickness of 2.6 ± 2.3 nm (<6 layers) and a lateral size of 490 ± 494 nm. Fe₂O₃ nanoparticles have an average size of 7.4 ± 3.0 nm. Fe₂O₃ nanoparticles on chemically and thermally stable MoS₂ nanosheets show catalytic activity in the glycolysis of polyethylene terephthalate (PET). High conversion of PET (97%) and a high yield (90%) for bis(hydroxyethyl) terephthalate (BHET) were achieved in a reaction time of 3 h at the reaction temperature of 225 °C.

Fe₂O₃@MoS₂ 0D/2D-nanocomposite material was synthesized in an aqueous solution using a Taylor–Couette flow reactor.

Interfacial Design on Graphene-Hematite Heterostructures for Enhancing Adsorption and Diffusion towards Superior Lithium Storage

Hematite (α-Fe₂O₃) is a promising electrode material for cost-effective lithium-ion batteries (LIBs), and the coupling with graphene to form Gr/α-Fe₂O₃ heterostructures can make full use of the merits of each individual component, thus promoting the lithium storage properties. However, the influences of the termination of α-Fe₂O₃ on the interfacial structure and electrochemical performance have rarely studied. In this work, three typical Gr/α-Fe₂O₃ interfacial systems, namely, single Fe-terminated (Fe-O₃-Fe-R), double Fe-terminated (Fe-Fe-O₃-R), and O-terminated (O₃-Fe-Fe-R) structures, were fully investigated through first-principle calculation. The results demonstrated that the Gr/Fe-O₃-Fe-R system possessed good structural stability, high adsorption ability, low volume expansion, as well as a minor diffusion barrier along the interface. Meanwhile, investigations on active heteroatoms (e.g., B, N, O, S, and P) used to modify Gr were further conducted to critically analyze interfacial structure and Li storage behavior. It was demonstrated that structural stability and interfacial capability were promoted. Furthermore, N-doped Gr/Fe-O₃-Fe-R changed the diffusion pathway and made it easy to achieve free diffusion for the Li atom and to shorten the diffusion pathway.