Nanostructured metal oxides with both anisotropic texture and hollow structures have attracted considerable attention with respect to improved electrochemical energy storage and enhanced catalytic activity. While synthetic strategies for the preparation of binary metal oxide hollow structures are well-established, the rational design and fabrication of complex ternary metal oxide with nonspherical hollow features is still a challenge. Herein, we report a simple and scalable strategy to fabricate highly symmetric porous ternary ZnxCo3-xO4 hollow polyhedra composed of nanosized building blocks, which involves a morphology-inherited and thermolysis-induced transformation of heterobimetallic zeolitic imidazolate frameworks. When tested as anode materials for lithium-ion batteries, these hollow polyhedra have exhibited excellent electrochemical performance with high reversible capacity, excellent cycling stability, and good rate capability.

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High symmetric porous Co3O4 hollow dodecahedra constructed by nanometer‐sized building blocks are rationally synthesized by templating against Co‐containing zeolitic imidazolate framework‐67. The well‐defined hollow structure and highly porous framework render these hollow dodecahedra exhibit high specific capacity, excellent cycling stability and superior rate capability when evaluated as an anode material for lithium‐ion batteries.

Vanadium dioxide (VO2) films with moth-eye nanostructures have been fabricated to enhance the thermochromic properties with different periodicity (d) to achieve antireflection (AR). It is revealed that the films with smaller d (210 and 440 nm) could increase both the luminous transmission (Tlum) and infrared transmission (TIR) at 25 and 90 °C, as the d is smaller than the given wavelength and the gradient refractive index produces antireflection. The average Tlum and TIR of VO2 increase with decreasing d. Compared with the planar film, the AR sample with periodicity of 210 nm and thickness of 140 nm can offer approximately 10% enhancement of Tlum and 24.5% increase in solar modulation (ΔTsol). With the addition of hydrophobic overcoat on the patterned VO2, ∼120° contact angle could be achieved. The present approach can tailor the optical transmittance in different wavelengths at high and low temperature together with self-cleaning, opening new avenues for producing hydrophobic VO2 with enhanced thermochromic properties for smart window applications.

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Highly dispersed Au nanoparticles have been immobilized on the Zr(IV)-based metal-organic framework UIO-66 via a simple one-step chemical wetting method, in which oleylamine used as both a reducing and a stabilizing agent with HAuCl 4 as the gold precursor is introduced to embed Au nanoparticles into the framework. The resulting Au@UIO-66 catalyst is characterized by powder X-ray diffraction, N 2 physical adsorption, and transmission electron microscopy. It is found that most of the Au nanoparticles with sizes of 1-3 nm are evenly distributed over the UIO-66 matrix. The Au@UIO-66 heterostructures exhibit high catalytic activity and stability for gas-phase CO oxidation. The observed high activity is mainly attributed to the small size of Au nanoparticles and their high dispersion within the pores of UIO-66.

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The water sensitivity of metal-organic frameworks (MOFs) poses a critical issue for their large-scale applications. One effective method to solve this is to provide MOFs with a hydrophobic surface. Herein, we develop a facile solution-immersion process to deposit a hydrophobic coating on the MOFs' external surface without blocking their intrinsic pores. The water contact angle of the surface hydrophobic (SH) MOFs is ∼146°. The hydrophobic coating not only greatly enhances MOFs' water stability but also provides durable protection against the attack of water molecules. When exposed to liquid water, the SH samples well retain their crystal structure, morphology, surface area and CO uptake capacity. However, the as-synthesized (AS) samples nearly collapse and lose their porosity as well as CO uptake capacity after the same exposure. This study opens up a new avenue for the MOFs' application of gas sorption in the presence of water.