Due to their special wetting properties, bioinspired superhydrophobic coatings are used to protect various materials. However, contamination with corrosive liquids or mechanical damage causes the loss of water repellency of many superhydrophobic surfaces. Therefore, it is imperative to develop chemically stable and durable superhydrophobic coatings. In this work, we report a straightforward method to fabricate a metal–organic framework (ZIF-8)/SiO2 with hierarchical micro-/nanostructures, whose surface hydrophobicity is induced by polydimethyl­siloxane (PDMS) modification. Notably, the surface of the resulting ZIF-8@SiO2/PDMS displays superhydrophobicity, together with a water contact angle (CA) of 157°. The superhydrophobic material is chemically stable, the water CA remaining above 150° even after exposure to a wide range of pH values (1–14) for 24 h. The electrochemical results showed that the coating exhibits a high corrosion potential (E corr = −0.321 V) and a very low corrosion current density (i corr = 1.442 × 10–11 A·cm–2) relative to an uncoated aluminum substrate (E corr = −0.711 V, i corr = 6.616 × 10–5 A·cm–2), indicating a high resistance to corrosion as a result of the coating. Also, electrochemical impedance spectroscopy showed that the charge transfer resistance is significantly increased by the coating. These results indicate that the ZIF-8@SiO2/PDMS coating with superhydrophobic properties has excellent corrosion resistance. In addition, the superhydrophobicity was proven for various droplets (i.e., water, tea, milk, coffee), an achievement related to the excellent self-cleaning performance: when the droplets roll off, surface contaminants are easily removed. The coating exhibited good mechanical properties, the CA being above 150° after 100 cycles of scrubbing with a pressure of 20 kPa. These excellent properties recommend the obtained superhydrophobic coating for various practical applications.

Metal halide perovskite with a suitable energy band structure and excellent visible-light response is a prospective photocatalyst for CO2 reduction. However, the reported inorganic halide perovskites have undesirable catalytic performances due to phase-sensitive and severe charge carrier recombination. Herein, we anchor the FAPbBr3 quantum dots (QDs) on Ti3C2 nanosheets to form a FAPbBr3/Ti3C2 composite within a Schottky heterojunction for photocatalytic CO2 reduction. Upon visible-light illumination, the FAPbBr3/Ti3C2 composite photocatalyst exhibits an appealing photocatalytic performance in the presence of deionized water. The Ti3C2 nanosheet acts as an electron acceptor to promote the rapid separation of excitons and supply specific catalytic sites. An optimal electron consumption rate of 717.18 μmol/g·h is obtained by the FAPbBr3/0.2-Ti3C2 composite, which has a 2.08-fold improvement over the pristine FAPbBr3 QDs (343.90 μmol/g·h). Meanwhile, the FAPbBr3/Ti3C2 photocatalyst also displays a superior stability during photocatalytic reaction. This work expands a new insight and platform for designing superb perovskite/MXene-based photocatalysts for CO2 reduction.

Compared with optical black, few attempts have focused on achieving broadband microwave blackbodies. In this study, all‐ceramic metamaterial microwave blackbodies are created by integrating a graded Gyroid shellular (GGS) metastructure design with additive manufacturing of polymer‐derived SiOC (PDCs‐SiOC) ceramics encapsulated by Si3N4 (SiOC@Si3N4). Hardly influenced by the destructive interference effect, as‐fabricated GGS‐structured SiOC@Si3N4 microwave blackbodies demonstrate a broadband microwave absorption (MA) above 83.6% (91.3% on average) across the entire X‐Ku band and encompassing higher frequencies above 18 GHz as well, together with the temperature insensitivity from room temperature to 500 °C. Based on the flexible electromagnetic tunability of PDCs‐SiOC, exceptional structural scalability is experimentally validated for metal‐doped modified CuSiOC and CoSiOC substrates with the same GGS metastructures, retaining high‐efficiency MA capability. Furthermore, attachment of perfectly reflecting metal backplanes further enhances the MA performance, with an ultrawide MA exceeding 67.9% (89.1% on average) achievable at 2.95–18 GHz for CoSiOC substrate. Meanwhile, the GGS‐structured SiOC@Si3N4 metamaterials possess additional multifunctional properties, such as good noise reduction performance as well as ultrahigh wear resistance. As a proof of concept, this study provides important guidance on achieving multifunctional coupling broadband MA characteristics by fully tapping the application potential of existing materials.

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