Metastable iron(iii) oxide polymorphs derived from Fe/Mn bimetallic coordination polymer particles in confined space: SiO2 shell effect on crystal phase transition

It is experimentally demonstrated that the coated SiO₂ shell has an influence on the kinetics of the polymorphous transition of iron(iii) oxides with manganese ions derived from coordination polymer particles, generating a meta-stable bixbyite crystal phase structure.

Amorphous Bimetallic Oxide-Graphene Hybrids as Bifunctional Oxygen Electrocatalysts for Rechargeable Zn-Air Batteries

Metal oxides of earth-abundant elements are promising electrocatalysts to overcome the sluggish oxygen evolution and oxygen reduction reaction (OER/ORR) in many electrochemical energy-conversion devices. However, it is difficult to control their catalytic activity precisely. Here, a general three-stage synthesis strategy is described to produce a family of hybrid materials comprising amorphous bimetallic oxide nanoparticles anchored on N-doped reduced graphene oxide with simultaneous control of nanoparticle elemental composition, size, and crystallinity. Amorphous Fe_0.5 Co_0.5 O_x is obtained from Prussian blue analog nanocrystals, showing excellent OER activity with a Tafel slope of 30.1 mV dec^-1 and an overpotential of 257 mV for 10 mA cm^-2 and superior ORR activity with a large limiting current density of -5.25 mA cm^-2 at 0.6 V. A fabricated Zn-air battery delivers a specific capacity of 756 mA h g_Zn^-1 (corresponding to an energy density of 904 W h kg_Zn^-1 ), a peak power density of 86 mW cm^-2 and can be cycled over 120 h at 10 mA cm^-2 . Other two amorphous bimetallic, Ni_0.4 Fe_0.6 O_x and Ni_0.33 Co_0.67 O_x , are also produced to demonstrate the general applicability of this method for synthesizing binary metal oxides with controllable structures as electrocatalysts for energy conversion.

Nano Metal-Organic Framework-Derived Inorganic Hybrid Nanomaterials: Synthetic Strategies and Applications

Nano- (or micro-scale) metal-organic frameworks (NMOFs), also known as coordination polymer particles (CPPs), have received much attention because of their structural diversities and tunable properties. Besides the direct use, NMOFs can be alternatively used as sacrificial templates/precursors for the preparation of a wide range of hybrid inorganic nanomaterials in straightforward and controllable manners. Distinct advantages of using NMOF templates are correlated to their structural and functional tailorability at molecular levels that is rarely acquired in any other conventional template/precursor. In addition, NMOF-derived inorganic nanomaterials with distinct chemical and physical properties are inferred to dramatically expand the scope of their utilization in many fields. In this review, we aim to provide readers with a comprehensive summary of recent progress in terms of synthetic approaches for the production of diverse inorganic hybrid nanostructures from as-synthesized NMOFs and their promising applications.

Magnetic ground state of nanosized β-Fe2O3 and its remarkable electronic features

In this study, we report on structural, magnetic, and electric features of β-Fe₂O₃ identifying its magnetic ground state and its potentiality in photoelectrochemical applications.