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Graphene has been widely used in the field of electromagnetic wave (EMW) absorption because it has many excellent properties, such as excellent electrical conductivity, large specific surface area, and good mechanical properties. However, the high conductivity and single loss mechanism lead to poor impedance matching and microwave absorption performance. Herein, we developed a strategy to introduce g-C3N4 nanosheet to combine with graphene oxide (GO) to enhance the heterojunction interfaces, thus bringing abundant interfacial polarization loss. Moreover, the excessive electrons on GO can be transferred to g-C3N4 through the electrostatic interaction between the g-C3N4 and GO layers. And on this basis, we designed g-C3N4-rGO into an aerogel structure to endow the material with a plentiful porous structure, which promotes the reflection and scattering of electromagnetic waves. In addition, the electromagnetic parameters of the material are adjusted by controlling the weight ratio of g-C3N4 and GO, as well as the calcination temperatures, to obtain a material with both excellent impedance matching and microwave absorbing properties. As a result, the synthesized aerogel shows remarkable EMW absorption performance with a broad effective absorption bandwidth (EAB) of 8.08 GHz and a reflection loss (RL) of −38.08 dB. To sum up, this work provides inspiration and guidance for designing nanomaterials with both outstanding impedance matching and microwave absorption performance. [ABSTRACT FROM AUTHOR]

Herein, a new strategy for improving epoxy coatings' anti‐corrosion performance has been developed, which combined NH2‐Ce‐MOF with graphene oxide (GO) by hydrothermal method. First, the nanocomposite material's morphology and structure (GO‐Ce‐MOF) were confirmed by Fourier transform infrared, X‐ray diffraction, TG, X‐ray photoelectron spectroscopy, and scanning electron microscope (SEM) studies. The dispersity of the composite in the epoxy coating was evaluated by SEM and mapping analysis. Meanwhile, the anti‐corrosion of as‐prepared composite coatings was investigated in detail by the electrochemical impedance spectroscopy (EIS) and the Tafel polarization curve test. The results illustrated that 2.0 wt% GO‐Ce‐MOF/EP greatly enhanced the composite coating's anti‐corrosion performance compared to other coatings. The reasons for the improvement of the anti‐corrosion performance of the composite coating are attributed to the following two aspects: On the one hand, the addition of GO can provide a physical barrier to form a labyrinth effect to slow down the invasion of corrosive media into the metal substrate, on the other hand, the modification of GO can GO‐Ce‐MOF achieve better compatibility and dispersion in epoxy resin. [ABSTRACT FROM AUTHOR]

Chitosan (CS) was used as a cross‐linking agent to modify UiO‐66‐NH2, and the modified UiO‐66‐NH2 was fixed on the mixed cellulose membrane (MCE) through vacuum filtration technology to prepare a new type of membrane. The membrane exhibited excellent hydrophilicity in the air and excellent super‐oleophobic performance underwater, and effectively separated various oil–water emulsions. When separating petroleum ether‐water emulsion, the filtration flux of the modified membrane was 2000 L m−2 h−1 higher than that of MCE, and the separation efficiency can reach more than 95%. After 10 cycles, the flux of the modified membrane was about four times of that MCE, which was 500 L m−2 h−1. Most importantly, the membrane still maintained underwater superoleophobicity in the environment of strong acid, strong base, and salt solution. [ABSTRACT FROM AUTHOR]

Herein, a new strategy for improving anti-corrosion performance of epoxy coatings has been developed, which combined halloysite nanotubes (HNTs) with graphene oxide (GO). On one hand, the corrosion inhibitors loaded in nanocontainers will be released in the event of a coating damage that will subsequently prevent metal from further corrosion because of the pH-responsive ability of the nanocomposite. On the other hand, GO exerts the physical barrier property to protect metal matrix against corrosive medium. This endows the coating system with both active and passive protection performances. The release behavior of BTA loaded in the lumen of the HNTs was determined by UV–vis, and the dispersity of the composite in epoxy coating was evaluated by SEM. Electrochemical impedance spectroscopy (EIS) confirmed that the BTA@HNTs-GO hybrid composite has an excellent anti-corrosion performance. [ABSTRACT FROM AUTHOR]