(PDA) coating can be used as an extremely versatile platform for tailoring of the coatings for diverse functional uses. Herein, we are inspired from the unique hierarchical structure of lotus leaf and the strong adhesion of mussel adhesive protein to simply develop a kind of superior superhydrophobic melamine foam through constructing a dopamine-induced lotus-leaf-like structure on melamine foam surface. Here, we choose the melamine foam (denoted MF foam) as an ideal starting material due to its commercial availability, low cost, good fl ame retardant, [ 22 ] light weight, high porosity, and robustness, all of which are highly desirable in a high-performance applied absorbent.With the combination of the amazing natural phenomena and the advanced material, a simple and mild three-step strategy is used to prepare the superhydrophobic foam. First, PDA coating proceeds through the simple dip-coating of the original hydrophilic MF foam in a basic solution of dopamine. Subsequently, the silver nanoparticles (Ag NPs) are formed by reduction and well distributed on the surface of PDA-coated MF foam. Finally, alkanethiol (1H, 1H, 2H, 2H-perfl uorodecanethiol) is used as hydrophobic molecules with low surface energy to react with both PDA and Ag NPs. After being modifi ed, the superhydrophobic MF foam is produced and exhibits excellent absorption and mechanical performances, including a high absorption capacity, robust stability, and extraordinary recyclability. The whole procedure was carried out under a mild condition and no special equipment was necessary. Furthermore, this approach is much more convenient, economical, and environmentally friendly than conventional processes for surface modifi cation. We believe that such biomimic novel superhydrophobic MF foam with high performance will have promising potential for practical applications and environmental protection.The mechanism of dopamine coating in basic solution is still disputed (e.g., supramolecular aggregation or polymerization), but the generally proposed and accepted one is the Michaeladdition reaction, in which the initial step involves an oxidation process between dopamine and O 2 . [ 23 ] With this inspiration, we found that high O 2 concentration in dopamine solution can extremely accelerate the PDA deposition process. Figure 1 a shows the dopamine concentration in solution decreases rapidly within 2 h under pure O 2 environment compared to that in ambient air. This agrees with the color change of dopamine solution quite well, as shown in Figure 1 b,c. Interestingly, MF foam shows excellent absorption to dopamine, the dopamine solution is still transparent even after stirring overnight. Moreover, the strong adhesion ability of PDA is confi rmed by ultrasonic treatment (See Movie S1, Supporting Information). The fast PDA deposition in the presence of pure O 2 and strong adhesion ability extremely favor its practical and industrial applications.Confronting the increasing environmental and ecological issues like the largest oil spillage event that happened i...

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Oxygen-containing functional groups tend to induce a strong interaction between solid adsorbents and iodine molecules, yet have not been systematically investigated. Herein, on the basis of a series of nitric acid-treated graphene oxide (GO) with different contents of oxygen functional groups for iodine adsorption, it was found that the iodine uptake capacity is proportionate to the oxygen content and the diversities of oxygen-containing groups. The density functional theory (DFT) calculation results also suggest that oxygen-containing groups result in strong interactions between iodine molecules and the adsorbents through a covalent bond-forming process, among which -OH groups possess a higher adsorption energy averagely. Such theoretical and experimental work deepens our understanding of the effects of oxygen functional groups on iodine adsorption and provides novel ideas for future design and synthesis of high-performance solid adsorbents for radioactive iodine.