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Now that there are various routes to prepare superhydrophobic surfaces for self-cleaning, anti-icing, liquid collecting, etc., attentions are moving toward low-cost upscaling of routes and increasing the reliability for actual applications. However, the required micro-nano structures for superhydrophobicity are light scattering and very vulnerable to abrasion. This intrinsically conflicts with the transparency and durability of superhydrophobic glass, which are the major barriers for its commercialization. In this study, we present a novel sequentially reinforced additive coating (SRAC) process to realize robust and transparent micro-nano structured film with tough intergranular sintering. A benign aqueous-based ink with poly(furfuryl alcohol) (PFA) and silica species is carefully designed and sprayed on glass to enable self-phase separation and morphology construction. The coatings reach the static contact angle (SCA) for water over 166° and withstand a 6H pencil scratching, the cross-cut test, and sand abrasion. Moreover, we also performed a 90 day outdoor performance test and the glass maintained superhydrophobicity with an SCA of 154°. These results provide a low-cost waterborne ink formula, and the high throughput and upscalable SRAC process could be a convenient technology for the fabrication of large area, robust superhydrophobic coatings.

Few-layer organic nanosheets are becoming increasingly attractive as two-dimensional (2D) materials due to their precise atomic connectivity and tailor-made pores. However, most strategies for synthesizing nanosheets rely on surface-assisted methods or top-down exfoliation of stacked materials. A bottomup approach with well-designed building blocks would be the convenient pathway to achieve the bulk-scale synthesis of 2D nanosheets with uniform size and crystallinity. Herein, we have synthesized crystalline covalent organic framework nanosheets (CONs) by reacting tetratopic thianthrene tetraaldehyde (THT) and aliphatic diamines. The bent geometry of thianthrene in THT retards the out-ofplane stacking, while the flexible diamines introduce dynamic characteristics into the framework, facilitating nanosheet formation. Successful isoreticulation with five diamines with two to six carbon chain lengths generalizes the design strategy. Microscopic imaging reveals that the odd and even diamine-based CONs transmute to different nanostructures, such as nanotubes and hollow spheres. The single-crystal X-ray diffraction structure of repeating units indicates that the odd−even linker units of diamines introduce irregular−regular curvature in the backbone, aiding such dimensionality conversion. Theoretical calculations shed more light on nanosheet stacking and rolling behavior with respect to the odd−even effects.

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Robust transparent superamphiphobic films are prepared by spray coating of designed micro-nano silica building blocks. The mechanical enhancement and photocatalytic properties are achieved for the films through effective titania bonding.

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Nine kinds of LDHs were synthesized by the co-precipitation method under alkaline conditions with different combinations of trivalent metal compounds (FeCl, AlCl, CoCl) and divalent metal compounds (CaCl, MgCl, ZnCl), which were then coated in situ on the surface of zeolites to synthesize core-shell zeolites/LDHs composites. The zeolites before and after modification were characterized by SEM and X-ray fluorescence spectrometry. Using the different core-shell zeolites/LDHs and original zeolite substrates, the constructed rapid infiltration systems (CRIS) simulated test columns were set to treat the municipal sewage containing hexavalent chromium, Cr(VI). Isothermal adsorption tests were subsequently performed. The average removal efficiencies of the small-sized zeolites were much higher than those of the large-sized zeolites. For the small-sized zeolites, the Cr(VI) removal performances of the Mg-LDHs- and Al-LDHs-modified zeolite substrates were efficiently enhanced in particular, which could reach over 90%. And the removal rate of core-shell zeolites/ZnAl-LDHs reached 94.5%. Meanwhile, the maximum adsorption capacity of ZnAl-LDHs-modified zeolites could reach 51.0 mg/kg, indicating that the adsorption properties could be enhanced by ZnAl-LDHs coating. During the purification experiments, most of the LDHs-modified zeolites maintained their predominant chemical adsorption ability for the removal of Cr(VI). Therefore, the small-sized core-shell zeolites/ZnAl-LDHs composites could be used as potential substrates for the efficient removal of Cr(VI) in CRIS.